9,694 results match your criteria Acta physiologica Scandinavica[Journal]


Comparison on plasma caesium kinetics in goats and horses with special emphasis on exercising horses.

Acta Physiol Scand 2005 Dec;185(4):335-40

Department of Basic Veterinary Sciences, University of Helsinki, Helsinki, Finland.

Aims: Like potassium (K+), caesium (Cs+) tends to concentrate intracellularly. The aim here was to determine how moderate exercise affects the uptake of Cs+ from blood plasma.

Methods: After an intravenous Cs+ dose of 5 micromol kg(-1), plasma Cs+ concentration was followed for 100 min in goats and for 60 min in horses. Read More

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http://dx.doi.org/10.1111/j.1365-201X.2005.01489.xDOI Listing
December 2005

Protein kinases A and C stimulate the Na+ active transport in frog skeletal muscle without an appreciable change in the number of sarcolemmal Na+ pumps.

Authors:
R A Venosa

Acta Physiol Scand 2005 Dec;185(4):329-34

Centro de Investigaciones Cardiovasculares, Facultad de Ciencias Médicas de la Universidad Nacional de La Plata, La Plata, Argentina.

Aim: The activation of both protein kinases A (PKA) and protein kinases C (PKC) in some cell types increases and in others reduces active Na+ efflux. These effects have been ascribed to either a change in the rate of ionic translocation by a fixed number of Na+ pumps or, a change in the number of plasma membrane pumps. The purpose of the present experiments was to study the effect of activating PKA and PKC on the Na+ extrusion by the Na+ pump in frog skeletal muscle. Read More

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http://dx.doi.org/10.1111/j.1365-201X.2005.01493.xDOI Listing
December 2005

Neuromuscular function during prolonged pedalling exercise at different cadences.

Authors:
G Sarre R Lepers

Acta Physiol Scand 2005 Dec;185(4):321-8

INSERM ERM207, UFR STAPS, Université de Bourgogne, Dijon Cedex, France.

Aim: The purpose of the present work was to assess the strategies set by the central nervous system in order to provide the power output required throughout a prolonged (1-h) pedalling exercise performed at different cadences (50 rpm, 110 rpm and the freely chosen cadence).

Methods: Neuromuscular (NM) activity of vastus lateralis, rectus femoris, biceps femoris and gastrocnemius lateralis muscles was studied quantitatively [root-mean square (RMS) and mean power frequency (MPF)] and qualitatively (timing of onset and offset of muscle bursts during crank cycle).

Results: The present results showed that increased cadence resulted in earlier muscle activation in crank cycle. Read More

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http://dx.doi.org/10.1111/j.1365-201X.2005.01490.xDOI Listing
December 2005

A single bout of exercise is followed by a prolonged decrease in the interstitial glucose concentration in skeletal muscle.

Authors:
J Henriksson M Knol

Acta Physiol Scand 2005 Dec;185(4):313-20

Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden.

Aim: The present study was performed to test the hypothesis that the interstitial glucose concentration in human skeletal muscle is decreased for a prolonged period following a single bout of exercise, while blood flow has returned to resting levels.

Methods: Muscle interstitial concentrations of glucose, lactate, pyruvate and urea were monitored in six healthy individuals during 8 h following a 2-h one-leg exercise session by microdialysis at low perfusion flow rate. Simultaneously the blood flow was measured by the microdialysis ethanol technique. Read More

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http://dx.doi.org/10.1111/j.1365-201X.2005.01498.xDOI Listing
December 2005

Escherichia coli derived factors modulate human granulosa cell steroidogenesis.

Acta Physiol Scand 2005 Dec;185(4):303-12

Department of Gynecological Endocrinology and Reproductive Medicine, University of Bonn, Bonn, Germany.

Aim: In order to identify bacterial compounds which directly affect granulosa cell steroidogenesis, the effect of culture-supernatants and extracts from Escherichia coli were tested in an in vitro granulosa cell culture model.

Methods: Samples were drawn from the culture-supernatant of E. coli ATCC25922 cultured in Luria-broth medium. Read More

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http://dx.doi.org/10.1111/j.1365-201X.2005.01497.xDOI Listing
December 2005

Novel Brugada syndrome-causing mutation in ion-conducting pore of cardiac Na+ channel does not affect ion selectivity properties.

Acta Physiol Scand 2005 Dec;185(4):291-301

Experimental and Molecular Cardiology Group, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.

Aim: Brugada syndrome is an inherited cardiac disease with an increased risk of sudden cardiac death. Thus far Brugada syndrome has been linked only to mutations in SCN5A, the gene encoding the alpha-subunit of cardiac Na+ channel. In this study, a novel SCN5A gene mutation (D1714G) is reported, which has been found in a 57-year-old male patient. Read More

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http://dx.doi.org/10.1111/j.1365-201X.2005.01496.xDOI Listing
December 2005
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Ion channel regulation of the dynamical instability of the resting membrane potential in saccular hair cells of the green frog (Rana esculenta).

Acta Physiol Scand 2005 Dec;185(4):271-90

IMB, Physiology & Pharmacology, University of Southern Denmark, Odense, Denmark.

Aims: We investigated the ion channel regulation of the resting membrane potential of hair cells with the aim to determine if the resting membrane potential is poised close to instability and thereby a potential cause of the spontaneous afferent spike activity.

Methods: The ionic mechanism and the dynamic properties of the resting membrane potential were examined with the whole-cell patch clamp technique in dissociated saccular hair cells and in a mathematical model including all identified ion channels.

Results: In hair cells showing I/V curves with a low membrane conductance flanked by large inward and outward rectifying potassium conductances, the inward rectifier (K(IR)), the delayed outward rectifier (K(V)) and the large conductance, calcium-sensitive, voltage-gated potassium channel (BK(Ca)) were all activated at rest. Read More

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http://dx.doi.org/10.1111/j.1365-201X.2005.01495.xDOI Listing
December 2005
1 Read

Gene expression profiling of exercise-induced cardiac hypertrophy in rats.

Acta Physiol Scand 2005 Dec;185(4):259-70

Institute of Health and Sport Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan.

Aims: Exercise training causes physiological cardiac hypertrophy, which acts to enhance cardiac function during exercise. However, the underlying molecular mechanisms are unclear. We investigated gene expression profile of exercise training-induced cardiac hypertrophy using left ventricle (LV) excised from exercise-trained and sedentary control rats (12-week old). Read More

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http://dx.doi.org/10.1111/j.1365-201X.2005.01494.xDOI Listing
December 2005

Respiratory muscle performance with stretch-shortening cycle manoeuvres: maximal inspiratory pressure-flow curves.

Acta Physiol Scand 2005 Nov;185(3):251-6

Department of Pathophysiology and Laiko General Hospital, University of Athens Medical School, Athens, Greece.

Aim: To test the hypothesis that the maximal inspiratory muscle (IM) performance, as assessed by the maximal IM pressure-flow relationship, is enhanced with the stretch-shortening cycle (SSC).

Methods: Maximal inspiratory flow-pressure curves were measured in 12 healthy volunteers (35 +/- 6 years) during maximal single efforts through a range of graded resistors (4-, 6-, and 8-mm diameter orifices), against an occluded airway, and with a minimal load (wide-open resistor). Maximal inspiratory efforts were initiated at a volume near residual lung volume (RV). Read More

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http://dx.doi.org/10.1111/j.1365-201X.2005.01486.xDOI Listing
November 2005

Saline-induced natriuresis and renal blood flow in conscious dogs: effects of sodium infusion rate and concentration.

Acta Physiol Scand 2005 Nov;185(3):237-50

Department of Physiology and Pharmacology, University of Southern Denmark, Odense, Denmark.

Aim: This study focused on static and dynamic changes in total renal blood flow (RBF) during volume expansion and tested whether a change in RBF characteristics is a necessary effector mechanism in saline-induced natriuresis.

Methods: The aortic flow subtraction technique was used to measure RBF continuously. Identical amounts of NaCl (2. Read More

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http://dx.doi.org/10.1111/j.1365-201X.2005.01480.xDOI Listing
November 2005

Mitochondrial efficiency in rat skeletal muscle: influence of respiration rate, substrate and muscle type.

Authors:
M Mogensen K Sahlin

Acta Physiol Scand 2005 Nov;185(3):229-36

Institute of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark.

Aim: To investigate the hypothesis that mitochondrial efficiency (i.e. P/O ratio) is higher in type I than in type II fibres during submaximal rates of respiration. Read More

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http://dx.doi.org/10.1111/j.1365-201X.2005.01488.xDOI Listing
November 2005

Effects of innervation state on Hsp25 content and phosphorylation in inactive rat plantaris muscles.

Acta Physiol Scand 2005 Nov;185(3):219-27

Department of Kinesiology, University of Illinois, Urbana, IL 61801, USA.

Aim: Previous reports suggest a role for neuromuscular activity levels and/or connectivity in modulating Hsp25 expression and phosphorylation (pHsp25) in skeletal muscles. However, pHsp25 has only been studied in denervated muscles and/or muscles exposed to high levels of residual neuromuscular activity. Spinal cord isolation (SI) provides a model in which the muscle is exposed to nearly complete inactivity with maintenance of the nerve-muscle connection. Read More

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http://dx.doi.org/10.1111/j.1365-201X.2005.01483.xDOI Listing
November 2005

Oxidative stress and nitric oxide synthase in skeletal muscles of rats with post-infarction, compensated chronic heart failure.

Acta Physiol Scand 2005 Nov;185(3):211-8

Department of Kinesiology, University of Waterloo, Waterloo, ON, Canada.

Aim: Involvement of oxidative stress and nitric oxide synthase (NOS) isoforms in skeletal muscle cellular adaptations to chronic heart failure (CHF) is controversial, and possible muscle fibre-type heterogeneity in the oxidative stress and NOS responses to CHF have not been examined. Consequently, we hypothesized that the changes in determinants of elevated oxidative and nitrosylative stress associated with CHF would occur in skeletal muscle and would be similar in predominantly type I slow twitch muscle (soleus) and type II fast twitch muscle (plantaris) of rats.

Methods: The purpose of this study was to measure NOS isoforms (endothelial, inducible and neuronal NOS) and antioxidant enzymes (SOD-1, SOD-2, catalase) by protein immunoblot as well as markers of oxidative stress by biochemical assays in soleus and plantaris muscle sections of the rat hind limb. Read More

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http://dx.doi.org/10.1111/j.1365-201X.2005.01479.xDOI Listing
November 2005

Effect of carbohydrate ingestion on brain exchange of amino acids during sustained exercise in human subjects.

Acta Physiol Scand 2005 Nov;185(3):203-9

Astrand Laboratory, University College of Physical Education and Sports, Stockholm, Sweden.

Aim: This study investigated the effect of prolonged exercise with and without carbohydrate intake on the brain exchange of amino acids, especially focussing on tryptophan and branched-chain amino acids (BCAA).

Methods: Five male subjects exercised for 3 h on a cycle ergometer at 200 +/- 7 W on two occasions; either supplemented with a 6% carbohydrate solution or with flavoured water (placebo). Catheters were inserted into the right internal jugular vein and the radial artery of the non-dominant arm. Read More

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http://dx.doi.org/10.1111/j.1365-201X.2005.01482.xDOI Listing
November 2005
4 Reads

Force-frequency relation in frog-ventricle is dependent on the direction of sodium/calcium exchange in diastole.

Acta Physiol Scand 2005 Nov;185(3):193-202

Department of Physiology, Christian Medical College, Vellore 632002, Tamil nadu, India.

Aim: Force of contraction increases with stimulus-frequency in mammalian and amphibian hearts under control conditions. Here, we have analysed the mechanism of the force-frequency relation (FFR) in frog-ventricle.

Methods: Circular strips of frog-ventricle were subjected to field-stimulation with frequencies in the range 0. Read More

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http://dx.doi.org/10.1111/j.1365-201X.2005.01487.xDOI Listing
November 2005

Left ventricular pressure-volume relationships during normal growth and development in the adult rat--studies in 8- and 50-week-old male Wistar rats.

Acta Physiol Scand 2005 Nov;185(3):181-91

Department of Cardiology, Leiden University Medical Center, Leiden, The Netherlands.

Aims: Left ventricular (LV) pressure-volume relations provide relatively load-independent indexes of systolic and diastolic LV function, but few data are available on pressure-volume relations during growth and development in the normal adult heart. Furthermore, to quantify intrinsic ventricular function the indexes should be normalized for heart weight. However, in many studies the indexes are reported in absolute terms, or body weight-correction is used as a surrogate for heart weight-correction. Read More

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http://doi.wiley.com/10.1111/j.1365-201X.2005.01484.x
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http://dx.doi.org/10.1111/j.1365-201X.2005.01484.xDOI Listing
November 2005
2 Reads

Arnold Heller and the lymph pump.

Authors:
K Aukland

Acta Physiol Scand 2005 Nov;185(3):171-80

Institute for Biomedicin, Physiology Section, University of Bergen, Bergen, Norway.

This article reviews studies on lymph propulsion in the lymph vessels by active contraction of the vessels, first described by Arnold Heller in 1869 in German language, and here translated into English. His observations were first confirmed by Beatrice Carrier (1926) and Howard Flory et al. (1927), and several groups were active up to World war II. Read More

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http://dx.doi.org/10.1111/j.1365-201X.2005.01470.xDOI Listing
November 2005

Low sodium intake induces an increase in renal monoamine oxidase activity in the rat. Involvement of an angiotensin II dependent mechanism.

Acta Physiol Scand 2005 Oct;185(2):161-7

Instituto de Investigaciones Médicas A. Lanari, University of Buenos Aires, Buenos Aires, Argentina.

Aims: The interplay between natriuretic dopamine and antinatriuretic angiotensin II represents an important mechanism for the regulation of renal sodium and water excretion. Monoamine oxidase is the main metabolizing pathway for dopamine in the renal cortex. In this study, we have analysed the effect of low sodium feeding and AT1 receptor blockade on renal dopamine metabolism by monoamine oxidase. Read More

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http://dx.doi.org/10.1111/j.1365-201X.2005.01473.xDOI Listing
October 2005

Relaxant effects of beta-adrenergic agonists on porcine and human detrusor muscle.

Acta Physiol Scand 2005 Oct;185(2):151-9

Department of Urology, University Hospital Mannheim, Theodor-Kutzer-Ufer 1-3, Mannheim, Germany.

Aim: Relaxant effects of different beta-adrenoceptor agonists on porcine and human detrusor were examined. Thus, the beta-adrenoceptor subtype mainly responsible for relaxation in the detrusor muscle of pigs was characterized. Additionally, different effects of several beta-agonists in both species were shown. Read More

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http://dx.doi.org/10.1111/j.1365-201X.2005.01474.xDOI Listing
October 2005

Muscle hypertrophy induced by the Ski protein: cyto-architecture and ultrastructure.

Acta Physiol Scand 2005 Oct;185(2):141-9

Department of Molecular Biosciences, University of Oslo, Blindern, Oslo, Norway.

Aim: Transgenic mice overexpressing the c-ski proto-oncogene driven by the MSV promoter undergo muscle hypertrophy, most notably fast fibres of the lower limb. This hypertrophy is not accompanied by a correspondingly large increase in force, and individual skinned muscle fibres exhibit a 30% reduction in force per cross-sectional area. In this respect, the MSV ski model is different from most other hypertrophy models and we here aim at describing the mechanisms for the reduced specific force. Read More

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http://doi.wiley.com/10.1111/j.1365-201X.2005.01462.x
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http://dx.doi.org/10.1111/j.1365-201X.2005.01462.xDOI Listing
October 2005

Duodenal secretion in humans mediated by the EP4 receptor subtype.

Acta Physiol Scand 2005 Oct;185(2):133-40

Department of Medicine M, Division of Gastroenterology, Glostrup University Hospital of Copenhagen, Copenhagen, Denmark.

Aim: Assessment of functional EP receptor subtypes involved in PGE2-induced secretion in human duodenum. The spectrum of activities by PGE2 in mammals, including cytoprotective bicarbonate secretion in duodenum, is mediated through four G protein-coupled receptor subtypes (EP1-EP4).

Methods: Biopsies from the second part of duodenum from patients undergoing endoscopy were mounted in modified Ussing chambers. Read More

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http://dx.doi.org/10.1111/j.1365-201X.2005.01471.xDOI Listing
October 2005

Exhaled nitric oxide during normoxic and hypoxic exercise in endurance athletes.

Acta Physiol Scand 2005 Oct;185(2):123-31

Laboratoire HP2, Faculté de Médecine, Université Joseph Fourier, 38700 La Tronche, France.

Aim: Endogenous nitric oxide (NO) through its relaxing effect on smooth muscle cells may be involved in pulmonary gas exchange as well as in the modulation of the hypoxic pulmonary vasoconstriction. As athletes with exercise-induced hypoxaemia (EIH) present pulmonary gas exchange abnormalities in normoxia that could be even greater in hypoxia, we hypothesized that pulmonary NO may be lower in such athletes with EIH.

Methods: Eleven athletes with EIH [decrease in arterial oxygen blood partial pressure (PaO2) > 12 mmHg] and 9 without EIH (NEIH) exercised at 40%, 60% (10 min) and 90% (5 min) of normoxic maximal power output (Pmax) in normoxia, and at 40% and 60% (10 min) of Pmax in hypoxia (FiO2 = 15%). Read More

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http://dx.doi.org/10.1111/j.1365-201X.2005.01475.xDOI Listing
October 2005
1 Read

Countercurrent compartmental models describe hind limb skeletal muscle helium kinetics at resting and low blood flows in sheep.

Acta Physiol Scand 2005 Oct;185(2):109-21

Anaesthesia & Intensive Care, The University of Adelaide, Adelaide, Australia.

Aims: This study evaluated the relative importance of perfusion and diffusion mechanisms in compartmental models of blood : tissue helium exchange in a predominantly skeletal muscle tissue bed in the sheep hind limb. Helium has different physiochemical properties from previously studied gases and is a common diluent gas in underwater diving where decompression schedules are based on theoretical models of inert gas kinetics.

Methods: Helium kinetics across skeletal muscle were determined during and after 20 min of helium inhalation, at separate resting and low steady-states of femoral vein blood flow in six sheep under isoflurane anaesthesia. Read More

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http://dx.doi.org/10.1111/j.1365-201X.2005.01481.xDOI Listing
October 2005

Melatonin-evoked potentiation of the juvenile rat tail artery neurogenic reactivity depends on degree of the change in the reactivity.

Acta Physiol Scand 2005 Oct;185(2):99-107

Laboratory of Circulation, Pavlov Institute of Physiology, St Petersburg, Russia.

Aim: Dependence of the melatonin-evoked potentiation of the rat tail artery neurogenic reactivity on degree of the change in the reactivity was studied.

Method: Electrical field stimulation-evoked contractile response of the juvenile rat tail artery segment under isometric conditions was recorded. 0. Read More

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http://dx.doi.org/10.1111/j.1365-201X.2005.01472.xDOI Listing
October 2005

The influence of endurance and resistance exercise on muscle capillarization in the elderly: a review.

Authors:
B A Harris

Acta Physiol Scand 2005 Oct;185(2):89-97

Faculty of Health Sciences, University of Sydney, Lidcombe and Australian College of Physical Education, Sydney Olympic Park, Australia.

Aim: Ageing is one of many factors altering skeletal muscle. Conflicting results from previous studies guided this review to identify what has been found to date regarding microvascular adaptations in skeletal muscle as the result of ageing or inactivity, and endurance or resistance training interventions. Additionally, this review attempts to identify the variety of parameters for determining capillarization and discuss why these might be contributing to the conflicting results. Read More

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http://dx.doi.org/10.1111/j.1365-201X.2005.01461.xDOI Listing
October 2005
6 Reads

Duodenal bicarbonate secretion--the prostaglandin receptor involved is EP4.

Authors:
Ove Lundgren

Acta Physiol Scand 2005 Oct;185(2):87

University of Göeborg, Göteborg, Sweden.

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http://dx.doi.org/10.1111/j.1365-201X.2005.01491_2.xDOI Listing
October 2005

Acute exercise causes an enhancement of tissue renin-angiotensin system in the kidney in rats.

Acta Physiol Scand 2005 Sep;185(1):79-86

Center for Tsukuba Advanced Research Alliance (TARA), University of Tsukuba, Tsukuba, Ibaraki, Japan.

Aims: Initially, the renin-angiotensin system (RAS) produced through the classical endocrine pathway was well known for its regulation of blood pressure. However, it was revealed that a local autocrine and/or paracrine RAS may exist in a number of tissues (such as kidney). Exercise causes a redistribution of tissue blood flow, by which the blood flow is greatly increased in active muscles, whereas it is decreased in the splanchnic circulation (such as in the kidney). Read More

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http://dx.doi.org/10.1111/j.1365-201X.2005.01459.xDOI Listing
September 2005

Expression and function of LAT1, a neutral amino acid exchanger, in renal porcine epithelial cell line LLC-PK.

Acta Physiol Scand 2005 Sep;185(1):71-8

Institute of Pharmacology and Therapeutics, Faculty of Medicine, Porto, Portugal.

Aim: The present study examined the expression of LAT1 and the functional characteristics of the inward and outward [14C] l-leucine transporter in the renal porcine epithelial cell line LLC-PK1.

Methods: LLC-PK1 cells were cultured in polycarbonate filters and accumulation and transepithelial flux of the substrate monitored with [14C] l-leucine. LAT1 transcripts were examined by RT-PCR. Read More

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http://dx.doi.org/10.1111/j.1365-201X.2005.01451.xDOI Listing
September 2005

Effects of 84-days of bedrest and resistance training on single muscle fibre myosin heavy chain distribution in human vastus lateralis and soleus muscles.

Acta Physiol Scand 2005 Sep;185(1):61-9

Human Performance Laboratory, Ball State University, Muncie, IN 47306, USA.

Aim: This investigation determined the effects of 84 days of bedrest on the composition of myosin heavy chain (MHC) in single skeletal muscle fibres with and without a resistance-training countermeasure programme.

Methods: Muscle biopsies were obtained from the m. vastus lateralis (VL) and m. Read More

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http://dx.doi.org/10.1111/j.1365-201X.2005.01457.xDOI Listing
September 2005
4 Reads

Doublets and low-frequency fatigue in potentiated human muscle.

Acta Physiol Scand 2005 Sep;185(1):51-60

UCB/UCSF Joint Graduate Group in Bioengineering, University of California at Berkeley, Berkeley, CA 94720-3140, USA.

Aim: To test the hypothesis that doublets compensate for low-frequency fatigue. Doublets increase force output from muscles stimulated at low frequencies. Low-frequency fatigue is a decline in the force elicited by low-frequency stimulation. Read More

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http://dx.doi.org/10.1111/j.1365-201X.2005.01456.xDOI Listing
September 2005

Glycogen depletion in intrafusal fibres in rats during short-duration high-intensity treadmill running.

Acta Physiol Scand 2005 Sep;185(1):41-50

Department of Life and Materials Engineering, Nagoya Institute of Technology, Nagoya, Japan.

Aim: The recruitment patterns of the intrafusal and extrafusal fibres in the soleus (SOL) and extensor digitorum longus (EDL) muscles of rats were investigated during brief-intensity exercise by assaying their glycogen content histochemically.

Methods: Six adult male rats were assigned to each of four groups that ran up a 6 degrees incline on a motor-driven treadmill, at 40 m min(-1) for either 0.5, 1, 2, or 4 min. Read More

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http://dx.doi.org/10.1111/j.1365-201X.2005.01455.xDOI Listing
September 2005

Ubiquitin targeting of rat muscle proteins during short periods of unloading.

Acta Physiol Scand 2005 Sep;185(1):33-40

EA 701, Muscle et pathologies chroniques, Institut de Biologie, 34060 Montpellier, France.

Aim: The ubiquitin-proteasome system is known to be involved in many situations leading to skeletal muscle atrophy. However, the cellular mechanisms triggering the atrophic process initiation are still poorly understood. For short periods of rat hindlimb unloading, we assessed the specific ubiquitin targeting of sarcoplasmic or myofibrillar proteins in slow and fast rat muscle types. Read More

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http://dx.doi.org/10.1111/j.1365-201X.2005.01446.xDOI Listing
September 2005
2 Reads

Acute myocardial ischaemia induces specific alterations of ventricular mitochondrial function in experimental pigs.

Acta Physiol Scand 2005 Sep;185(1):25-32

Service de Physiologie Clinique et des Explorations Fonctionnelles, Département de Physiologie, Faculté de Médecine, Strasbourg, France.

Aims: As cardiac metabolic flexibility is crucial, this study examined whether acute ischaemia can induce specific qualitative alterations of the mitochondrial metabolic pathways as well as energy transfer systems.

Methods: Left descending coronary artery ligation was performed after sternotomy in eight pigs and the heart was excised after 45 min of ischaemia. Maximal O2 uptake (V(max), micromol O2 min(-1) g(-1) dry weight) of saponin-skinned myofibres were measured from ischaemic and non-ischaemic area of ventricular myocardium. Read More

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http://dx.doi.org/10.1111/j.1365-201X.2005.01458.xDOI Listing
September 2005

Myocardial and coronary sinus purines as indicators of pig heart energy metabolism during reperfusion after extracorporeal circulation.

Acta Physiol Scand 2005 Sep;185(1):13-23

Department of Biochemistry and Chemistry, Pomeranian Medical University, Szczecin, Poland.

Aim: The precise understanding of myocardial metabolism is crucial for the optimization of cardiosurgical procedures. We attempted to gain a comprehensive insight into the purine metabolism of the porcine heart during reperfusion by measuring concentrations of nucleotides, nucleosides and oxypurines simultaneously in the myocardium and coronary sinus.

Methods: Twenty-five pigs were subjected to sham cardiosurgery with extracorporeal circulation and cold cardioplegic arrest of 60 min. Read More

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http://dx.doi.org/10.1111/j.1365-201X.2005.01454.xDOI Listing
September 2005

Platelet activating factor (PAF) increases plasma protein extravasation and induces lowering of interstitial fluid pressure (P) in rat skin.

Acta Physiol Scand 2005 Sep;185(1):5-12

Department of Biomedicine, Section for Physiology, University of Bergen, Bergen, Norway.

Aim: To investigate the ability of the microdialysis technique to measure capillary selectivity of different sized plasma proteins induced by local administration of platelet activating factor (PAF).

Methods: We used hollow plasmapheresis fibres with 3 cm membrane (cut off 3000 kDa) placed on the back of anaesthetized rats.

Results: Platelet activating factor (50 microg mL(-1)) administered locally via the fibre, increased extravasation of radiolabelled 125I-HSA from plasma to the microdialysis fibre by approximately 900% compared both to baseline and the control fibre within 70 min (n = 6, P < 0. Read More

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http://dx.doi.org/10.1111/j.1365-201X.2005.01453.xDOI Listing
September 2005

Fuel selection in shivering humans.

Authors:
J-M Weber F Haman

Acta Physiol Scand 2005 Aug;184(4):319-29

Faculty of Science (Biology), University of Ottawa, Ottawa, ON, Canada.

Heat exchange has been thoroughly studied in cold-exposed humans, but the metabolic substrates used for thermogenesis have received less attention. This review deals with oxidative fuel selection in shivering humans. Lipids provide most of the heat during low-intensity shivering, whereas carbohydrates become dominant under more extreme cold conditions. Read More

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http://dx.doi.org/10.1111/j.1365-201X.2005.01465.xDOI Listing

NEAT--non-exercise activity thermogenesis--egocentric & geocentric environmental factors vs. biological regulation.

Authors:
J A Levine C M Kotz

Acta Physiol Scand 2005 Aug;184(4):309-18

Endocrine Research Unit, Mayo Clinic and Mayo Foundation, Rochester, MN, USA.

Non-exercise activity thermogenesis (NEAT) is the energy expenditure of all physical activities other than volitional sporting-like exercise. NEAT includes all those activities that render us vibrant, unique and independent beings such as going to work, playing guitar, toe-tapping and dancing. The factors that account for the 2000 kcal day(-1) variability of NEAT can be categorized as environmental or biological. Read More

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http://doi.wiley.com/10.1111/j.1365-201X.2005.01467.x
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http://dx.doi.org/10.1111/j.1365-201X.2005.01467.xDOI Listing
August 2005
7 Reads

A role for suppressed skeletal muscle thermogenesis in pathways from weight fluctuations to the insulin resistance syndrome.

Authors:
A G Dulloo

Acta Physiol Scand 2005 Aug;184(4):295-307

Division of Physiology, Department of Medicine, University of Fribourg, Fribourg, Switzerland.

An impressive body of epidemiological evidence suggests that a history of large perturbations in body weight earlier in life, independently of excess weight, is a risk factor for later development of insulin-related complications, namely central obesity, type 2 diabetes and cardiovascular disease. Such an increased risk has been reported in men and women who in young adulthood experienced weight fluctuations that involved weight recovery after weight loss caused by disease, famine or voluntary 'yoyo' dieting, and is particularly strong when the weight fluctuations occurred much earlier in life and are characterized by catch-up growth after foetal and/or neonatal growth retardation. As the phase of weight recovery/catch-up growth is associated with both hyperinsulinaemia and an accelerated rate for recovering fat mass (i. Read More

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http://doi.wiley.com/10.1111/j.1365-201X.2005.01466.x
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http://dx.doi.org/10.1111/j.1365-201X.2005.01466.xDOI Listing
August 2005
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Endocrine and signalling role of adipose tissue: new perspectives on fat.

Authors:
P Trayhurn

Acta Physiol Scand 2005 Aug;184(4):285-93

Neuroendocrine and Obesity Biology Unit, Liverpool Centre for Nutritional Genomics, School of Clinical Sciences, University of Liverpool, Liverpool, UK.

White adipose tissue (WAT) is now recognized as a major endocrine and secretory organ, releasing a wide range of protein factors and signals termed adipokines - in addition to fatty acids and other lipid moieties. A paradigm shift came with the discovery of leptin, a pleiotropic hormone which is a critical signal to the hypothalamus in the control of appetite and energy balance. A number of adipokines, including adiponectin, tumour necrosis factor-alpha, interleukin (IL)-1beta, IL-6, IL-8, IL-10, monocyte chemoattractant protein-1, macrophage migration inhibitory factor, nerve growth factor, vascular endothelial growth factor, plasminogen activator inhibitor-1 and haptoglobin, are linked to inflammation and the inflammatory response. Read More

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http://dx.doi.org/10.1111/j.1365-201X.2005.01468.xDOI Listing
August 2005
4 Reads

Thyroid hormones as molecular determinants of thermogenesis.

Acta Physiol Scand 2005 Aug;184(4):265-83

Dipartimento di Scienze Biologiche ed Ambientali, Università degli Studi del Sannio, Benevento, Italy.

Thyroid hormones (TH) are major modulators of energy metabolism and thermogenesis. It is generally believed that 3,5,3'-triiodo-l-thyronine (T3) is the only active form of TH, and that most of its effects are mediated by nuclear T3 receptors, which chiefly affect the transcription of target genes. Some of these genes encode for the proteins involved in energy metabolism. Read More

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http://dx.doi.org/10.1111/j.1365-201X.2005.01463.xDOI Listing
August 2005
3 Reads

Pituitary and autonomic responses to cold exposures in man.

Acta Physiol Scand 2005 Aug;184(4):255-64

Department of Physiology and Centre for Arctic Medicine, University of Oulu, Oulun yliopisto, Finland.

This review presents hormonal responses to various cold exposures and their calorigenic effects in man and some animals. Previous studies in rats have shown that cold exposures activate the hypothalamic-pituitary-thyroid axis. Increased thyroid hormone concentrations lead to heat production via general stimulation of metabolism (obligatory thermogenesis) and possibly via activation of thyroid hormone receptors and uncoupling protein 1 (UCP 1) and deiodinase enzyme genes in the brown adipose tissue (BAT). Read More

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http://dx.doi.org/10.1111/j.1365-201X.2005.01464.xDOI Listing
August 2005
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Nitrite transport into pig erythrocytes and its potential biological role.

Authors:
F B Jensen

Acta Physiol Scand 2005 Jul;184(3):243-51

Institute of Biology, University of Southern Denmark, Odense, Denmark.

Aim: To study nitrite transport and its oxygenation dependency in pig erythrocytes, as this is fundamental to the possible participation of nitrite in blood flow regulation via its reduction to nitric oxide by deoxygenated haemoglobin (Hb).

Methods: Pig red blood cells (RBCs) were tonometer-equilibrated to physiological pCO2 in oxygenated and deoxygenated states. Nitrite was added and the kinetics of NO2- influx and methaemoglobin (metHb) formation were assessed at variable temperature and haematocrit. Read More

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http://dx.doi.org/10.1111/j.1365-201X.2005.01448.xDOI Listing

Skeletal muscle contractility is preserved in COPD patients with normal fat-free mass.

Acta Physiol Scand 2005 Jul;184(3):235-42

Department of Physiology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands.

Aim: Peripheral muscle dysfunction often occurs in patients with chronic obstructive pulmonary disease (COPD). The muscle dysfunction may be caused by a loss of force-generating capacity, resulting from a loss of muscle mass, as well as by other alterations in contractile properties of skeletal muscle.

Methods: The maximal isometric voluntary strength and fatigability were determined in hand-grip and quadriceps muscles from nine male COPD patients (FEV(1) 30-50% predicted) and control subjects matched for fat-free mass (FFM), physical activity level and age. Read More

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http://dx.doi.org/10.1111/j.1365-201X.2005.01447.xDOI Listing
July 2005
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Effects of sodium intake on plasma potassium and renin angiotensin aldosterone system in conscious dogs.

Acta Physiol Scand 2005 Jul;184(3):225-34

Department of Physiology and Pharmacology, Institute of Medical Biology, University of Southern Denmark, Odense, Denmark.

Aims: The operating range of the renin-angiotensin-aldosterone system is ill-defined. This study quantifies renin-angiotensin-aldosterone system activity as a function of sodium intake.

Methods: Renin-angiotensin-aldosterone system variables were measured daily after a sudden reduction in sodium intake (3. Read More

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http://dx.doi.org/10.1111/j.1365-201X.2005.01452.xDOI Listing
July 2005
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Regulation of oxidative enzyme activity and eukaryotic elongation factor 2 in human skeletal muscle: influence of gender and exercise.

Acta Physiol Scand 2005 Jul;184(3):215-24

The Copenhagen Muscle Research Centre, Department of Human Physiology, Institute of Exercise and Sport Sciences, University of Copenhagen, Copenhagen, Denmark.

Aim: To investigate gender-related differences in the responses of oxidative enzymes and eukaryotic elongation factor-2 (eEF2) to exercise.

Methods: The influence of exercise (90 min, 60%VO(2peak)) on citrate synthase (CS) and beta-hydroxyacyl-CoA dehydrogenase (HAD) activity and mRNA content, together with eEF2 expression and phosphorylation at rest, were assessed in skeletal muscle of untrained (UT) and endurance trained (ET) females and males.

Results: Citrate synthase and HAD mRNA were higher in females than in males (27% and 48%, respectively, P < 0. Read More

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http://dx.doi.org/10.1111/j.1365-201X.2005.01442.xDOI Listing