58 results match your criteria reduced periarteriolar

Pro-Cellular Exhaustion Markers are Associated with Splenic Microarchitecture Disorganization and Parasite Load in Dogs with Visceral Leishmaniasis.

Sci Rep 2019 09 10;9(1):12962. Epub 2019 Sep 10.

Laboratório de Pesquisa em Leishmaniose, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil.

In canine visceral leishmaniasis (CVL), splenic white pulp (SWP) disorganization has been associated with disease progression, reduced cytokine and chemokine expression and failure to control the parasite load. This profile is compatible with the cellular exhaustion previously shown in human visceral leishmaniasis. The present study aimed to evaluate the in situ expression of cellular exhaustion markers and their relation to clinical signs, SWP disorganization and parasite load. Read More

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September 2019

The ATP-gated P2X ion channel contributes to the severity of antibody-mediated Transfusion-Related Acute Lung Injury in mice.

Sci Rep 2019 03 26;9(1):5159. Epub 2019 Mar 26.

Université de Strasbourg, INSERM, Etablissement Français du Sang (EFS) Grand Est, BPPS UMR_S 1255, Fédération de Médecine Translationnelle de Strasbourg (FMTS), F-67000, Strasbourg, France.

The biological responses that control the development of Transfusion-Related Acute Lung Injury (TRALI), a serious post-transfusion respiratory syndrome, still need to be clarified. Since extracellular nucleotides and their P2 receptors participate in inflammatory processes as well as in cellular responses to stress, we investigated the role of the ATP-gated P2X cation channel in antibody-mediated TRALI. The effects of NF449, a selective P2X1 receptor (P2RX1) antagonist, were analyzed in a mouse two-hit model of TRALI. Read More

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Nebulisation of synthetic lamellar lipids mitigates radiation-induced lung injury in a large animal model.

Sci Rep 2018 09 6;8(1):13316. Epub 2018 Sep 6.

The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh, United Kingdom.

Methods to protect against radiation-induced lung injury (RILI) will facilitate the development of more effective radio-therapeutic protocols for lung cancer and may provide the means to protect the wider population in the event of a deliberate or accidental nuclear or radiological event. We hypothesised that supplementing lipid membranes through nebulization of synthetic lamellar lipids would mitigate RILI. Following pre-treatment with either nebulised lamellar lipids or saline, anaesthetised sheep were prescribed fractionated radiotherapy (30 Gray (Gy) total dose in five 6 Gy fractions at 3-4 days intervals) to a defined unilateral lung volume. Read More

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September 2018

[Distinct vascular niches determine hematopoietic stem cell fate].

Yuya Kunisaki

Rinsho Ketsueki 2015 Jun;56(6):606-13

Kyushu University, Department of Medicine and Biosystemic Science / Center for Cellular and Molecular Medicine.

Identification of cellular constituents of the hematopoietic stem cell (HSC) niche has recently been the subject of intensive investigation. To investigate the spatial localization of the HSC niches in bone marrow, we have established a whole-mount immunofluorescence imaging technique in which the 3D spatial relationships between stromal structures and HSCs in the BM can be precisely determined. The imaging assessment combined with computational simulations has uncovered a significant association between HSCs and arterioles, ensheathed exclusively by rare Nestin(bright) NG2⁺ pericytes (Nes(peri) cells), distinct from sinusoid-associated Nestin(dim) Leptin receptor (LepR)⁺ (Nes(retic)) cells which reportedly represent peri-vascular niche cells. Read More

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Loss of sympathetic nerve fibers around intratumoral arterioles reflects malignant potential of gastric cancer.

Ann Surg Oncol 2011 Aug 3;18(8):2281-8. Epub 2011 Feb 3.

Department of Surgery, Division of Surgical Oncology, University of Tokyo, Tokyo, Japan.

Background: The role and clinical significance of the alteration of sympathetic nerve fibers (SNF) was assessed in gastric cancer. Loss of nerve fibers in malignant tumors has previously been described; however, how dysfunction of the nervous system is involved in cancer progression has not been clarified in clinical studies.

Materials And Methods: The distribution of SNF was examined in 82 surgically resected gastric cancer specimens with immunohistochemical staining of tyrosine hydroxylase (TH), and the association with clinicopathological findings as well as the clinical outcome of the patients was retrospectively evaluated. Read More

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[Maturation of dendritic cells and activation of B-lymphocytes in spleens of ICR mice infected with chloroquine-resistant Plasmodium berghei].

Zhongguo Ji Sheng Chong Xue Yu Ji Sheng Chong Bing Za Zhi 2008 Feb;26(1):1-5

School of Agriculture and Biology, Shanghai Jiaotong University, Shanghai 201101, China.

Objective: To investigate the relation between activation of B-cells and maturation of dendritic cells (DC) in the spleens of ICR mice infected with chloroquine-resistant (RC) or chloroquine-sensitive (N) strain of Plasmodium berghei.

Methods: Spleens were taken after the mice were infected with N or RC strains of P. berghei and attained certain degree of parasitemia. Read More

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February 2008

Cerebral microvascular nNOS responds to lowered oxygen tension through a bumetanide-sensitive cotransporter and sodium-calcium exchanger.

Am J Physiol Heart Circ Physiol 2008 May 7;294(5):H2166-73. Epub 2008 Mar 7.

Department of Cellular and Integrative Physiology, Indiana University Medical School, 635 Barnhill Drive, Indianapolis, IN 46202, USA.

Na(+) cotransporters have a substantial role in neuronal damage during brain hypoxia. We proposed these cotransporters have beneficial roles in oxygen-sensing mechanisms that increase periarteriolar nitric oxide (NO) concentration ([NO]) during mild to moderate oxygen deprivation. Our prior studies have shown that cerebral neuronal NO synthase (nNOS) is essential for [NO] responses to decreased oxygen tension and that endothelial NO synthase (eNOS) is of little consequence. Read More

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Extracellular arginine rapidly dilates in vivo intestinal arteries and arterioles through a nitric oxide mechanism.

Microcirculation 2008 Feb;15(2):123-35

Department of Cellular and Integrative Physiology, Indiana University Medical School, Indianapolis, IN 46202, USA.

Objective: Arginine used for nitric oxide formation can be from intracellular stores or transported into cells. The study evaluated the rapidity, and primary site of NO and vascular resistance responses to arginine at near physiological concentrations (100-400 microM).

Methods: Arginine was applied to a single arteriole through a micropipette to determine the fastest possible responses. Read More

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February 2008

Attenuation of NADPH oxidase activation and glomerular filtration barrier remodeling with statin treatment.

Hypertension 2008 Feb 2;51(2):474-80. Epub 2008 Jan 2.

University of Missouri-Columbia School of Medicine, Department of Internal Medicine, Division of Nephrology, MA436, DC043.0, One Hospital Dr, Columbia, MO 65212, USA.

Activation of reduced nicotinamide-adenine dinucleotide phosphate (NADPH) oxidase by angiotensin II is integral to the formation of oxidative stress in the vasculature and the kidney. 3-Hydroxy-3-methylglutaryl-coenzyme A reductase inhibition is associated with reductions of oxidative stress in the vasculature and kidney and associated decreases in albuminuria. Effects of 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibition on oxidative stress in the kidney and filtration barrier integrity are poorly understood. Read More

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February 2008

In vivo evidence that Sarcoptes scabiei (Acari: Sarcoptidae) is the source of molecules that modulate splenic gene expression.

J Med Entomol 2007 Nov;44(6):1054-63

Department of Biological Sciences, Wright State University, Dayton, OH 45435, USA.

The clinical signs of a Sarcoptes scabiei (De Geer) (Acari: Sarcoptidae) infestation are initially delayed, which suggests that the mites can depress the immune/inflammatory response. The purpose of this study was to investigate the modulatory properties of scabies mites in vivo at the gene expression level in a secondary lymphoid organ that is involved in initiating an immune response to the parasite. We found that substances from scabies mites influenced the expression of mRNA for molecules that participate in the sequestering of lymphocytes in the periarteriolar lymphoid sheath, primary follicle, and marginal zone of the spleen. Read More

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November 2007

Cerebral microvascular dilation during hypotension and decreased oxygen tension: a role for nNOS.

Am J Physiol Heart Circ Physiol 2007 Oct 13;293(4):H2193-201. Epub 2007 Jul 13.

Department of Cellular and Integrative Physiology, Indiana University Medical School, Indianapolis, Indiana 46202, USA.

Endothelial (eNOS) and neuronal nitric oxide synthase (nNOS) are implicated as important contributors to cerebral vascular regulation through nitric oxide (NO). However, direct in vivo measurements of NO in the brain have not been used to dissect their relative roles, particularly as related to oxygenation of brain tissue. We found that, in vivo, rat cerebral arterioles had increased NO concentration ([NO]) and diameter at reduced periarteriolar oxygen tension (Po(2)) when either bath oxygen tension or arterial pressure was decreased. Read More

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October 2007

Preservation of coronary reserve by ivabradine-induced reduction in heart rate in infarcted rats is associated with decrease in perivascular collagen.

Am J Physiol Heart Circ Physiol 2007 Jul 23;293(1):H590-8. Epub 2007 Mar 23.

Department of Biomedical Sciences, New York College of Osteopathic Medicine/NYIT, Old Westbury, NY 11568, USA.

We tested the hypothesis that chronically reducing the heart rate in infarcted middle-aged rats using ivabradine (IVA) would induce arteriolar growth and attenuate perivascular collagen and, thereby, improve maximal perfusion and coronary reserve in the surviving myocardium. Myocardial infarction (MI) was induced in 12-mo-old male Sprague-Dawley rats, which were then treated with either IVA (10.5 mg. Read More

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Endothelial nitric oxide synthase is a molecular vascular target for the Chinese herb Danshen in hypertension.

Am J Physiol Heart Circ Physiol 2007 May 15;292(5):H2131-7. Epub 2006 Dec 15.

Department of Pharmacology and Physiology, UMDNJ-New Jersey Medical School, 185 South Orange Avenue, Newark, NJ 07101-1709, USA.

Danshen, a Chinese herb, reduces hypertension in Oriental medicine. We hypothesized that Danshen acts partially through endothelial nitric oxide synthase (eNOS) signaling mechanisms. We tested the hypothesis using tanshinone II(A), an active ingredient of Danshen, and the two-kidney, one-clip renovascular hypertension model in hamsters. Read More

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Acupuncture reduces experimental renovascular hypertension through mechanisms involving nitric oxide synthases.

Microcirculation 2006 Oct-Nov;13(7):577-85

Program in Vascular Biology, Department of Pharmacology and Physiology, UMDNJ-New Jersey Medical School, Newark, 07101-1709, USA.

Objective: To test the hypothesis that acupuncture on stomach 36 point (ST-36) reduces hypertension by activating nitric oxide synthase signaling mechanisms.

Methods: The authors used the two-kidney, one-clip renal hypertension (2K1C) hamster model with electroacupuncture treatment.

Results: Thirty-minute daily electroacupuncture treatment for 5 days reduced mean arterial pressure from 160. Read More

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November 2006

Inflammatory lesion and parasite load are inversely associated in Leishmania amazonensis infected mice genetically selected according to oral tolerance susceptibility.

Microbes Infect 2006 Apr 9;8(4):957-64. Epub 2006 Feb 9.

Laboratório de Imunobiologia, Departamento Biologia Celular e Genética, Instituto de Biologia, Universidade do Estado do Rio de Janeiro, Rua S. Francisco Xavier, 524, PHLC, Maracanã, CEP 20559-900 Rio de Janeiro, Brazil.

Two strains of mice selected according to extreme phenotypes of susceptibility and resistance to oral tolerance (TS and TR mice, respectively) were infected with 1 x 10(7) Leishmania amazonensis promastigotes and studied comparatively. TS mice developed a minor pathology while permitting parasite growth with the presence of increased IL-4, IL-10 and IFN-gamma, and lower NO and IL-2 levels and delayed-type hypersensitivity (DTH). In contrast, in TR mice, footpad swelling was increased but parasite growth was reduced. Read More

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Evidence for benefits of perindopril in hypertension and its complications.

Am J Hypertens 2005 Sep;18(9 Pt 2):155S-162S

Department of Pharmacology and INSERM U652, Hôpital Européen Georges Pompidou, 20 rue Leblanc, 75015 Paris, France.

Structural and functional changes in large and small arteries in hypertension, even at early stages, may affect one or several end organs such as the brain, heart, and kidneys, contributing to cardiovascular morbidity and mortality. Therefore, modern treatment strategies should not only target blood pressure (BP) reduction but also normalize vascular structure and function. The purpose of this article is to review the large body of evidence, from randomized double-blind clinical trials, that has been gathered in regard to the angiotensin-converting enzyme (ACE) inhibitor perindopril, demonstrating its efficacy in reducing BP, reversing abnormalities of vascular structure and function in patients with essential hypertension, and ultimately preventing cardiovascular events. Read More

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September 2005

Swiss mice CD1 fed on mussels contaminated by okadaic acid and yessotoxins: effects on thymus and spleen.

Eur J Histochem 2005 Apr-Jun;49(2):179-88

Department of Animal Biology, University of Modena and Reggio Emilia, Modena, Italy.

The toxicity of okadaic acid (OA) and yessotoxins (YTXs) was studied in mice orally fed on (i) OA (17.80+/-2.41 microg/kg) for 24 h and mouse feed for 24 h; (ii) OA (17. Read More

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November 2005

Altered migration, recruitment, and somatic hypermutation in the early response of marginal zone B cells to T cell-dependent antigen.

J Immunol 2005 Apr;174(8):4567-78

Centenary Institute of Cancer Medicine and Cell Biology, Newtown, New South Wales, Australia.

The early responses of follicular (Fo) and marginal zone (MZ) B cells to T cell-dependent Ag were compared using anti-hen egg lysozyme (HEL+) B cells capable of class switch recombination and somatic hypermutation (SHM). Purified CD21/(35int)CD23high Fo and CD21/35(high)CD23low MZ splenic B cells from SW(HEL) Ig-transgenic mice were transferred into wild-type recipients and challenged with HEL-sheep RBC. Responding HEL+ B cells from both populations switched efficiently to IgG1, generated syndecan-1+ Ab-secreting cells, and exhibited equivalent rates of proliferation. Read More

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Validation of immune function testing during a 4-week oral toxicity study with FK506.

Toxicol Lett 2004 Apr;149(1-3):123-31

Novartis Pharma AG, Preclinical Safety, MUT-2881.329, Auhafenstrasse, CH-4132 Muttenz, Switzerland.

Assessment of the immune system's capability to respond to antigens with the generation of specific antibodies, whilst under the influence of a test article, is required in toxicity tests according to the European guideline for repeated dose toxicity testing of medicinal products. The purpose of this study in rats was to validate methodology for the determination of Keyhole Limpet Haemocyanin (KLH)-specific antibodies under the influence of an immunologically active compound. The immunosuppressant FK506, commercially available as Prograf, was administered orally (gavage) to five rats per sex per group at dosages of 0. Read More

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Reduced perivascular PO2 increases nitric oxide release from endothelial cells.

Am J Physiol Heart Circ Physiol 2003 Aug;285(2):H507-15

Dept. of Physiology and Biophysics, Indiana University School of Medicine, 635 Barnhill Drive, Indianapolis, IN 46202, USA.

Many studies have suggested that endothelial cells can act as "oxygen sensors" to large reductions in oxygen availability by increasing nitric oxide (NO) production. This study determined whether small reductions in oxygen availability enhanced NO production from in vivo intestinal arterioles, venules, and parenchymal cells. In vivo measurements of perivascular NO concentration ([NO]) were made with NO-sensitive microelectrodes during normoxic and reduced oxygen availability. Read More

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Essential role of RelB in germinal center and marginal zone formation and proper expression of homing chemokines.

J Immunol 2001 Aug;167(4):1909-19

Forschungszentrum Karlsruhe, Institute of Toxicology and Genetics, Karlsruhe, Germany.

High levels of the Rel/NF-kappaB family member RelB are restricted to specific regions of thymus, lymph nodes, and Peyer's patches. In spleen, RelB is expressed in periarteriolar lymphatic sheaths, germinal centers (GCs), and the marginal zone (MZ). In this study, we report that RelB-deficient (relB(-/-)) mice, in contrast to nfkb1(-/-), but similar to nfkb2(-/-) mice, are unable to form GCs and follicular dendritic cell networks upon Ag challenge in the spleen. Read More

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Repair of coronary arterioles after treatment with perindopril in hypertensive heart disease.

Hypertension 2000 Aug;36(2):220-5

Department of Cardiology, Pneumology and Angiology, Heinrich-Heine University, Düsseldorf, Germany.

In hypertensive heart disease, no data are available on the repair of coronary resistance vessels in patients after long-term ACE inhibitor treatment. Fourteen patients with essential hypertension were studied with coronary flow reserve and with transvenous endomyocardial biopsy before and after 12 months of antihypertensive treatment with perindopril (4 to 8 mg/d, mean 5.9+/-2. Read More

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Growth plate compressions and altered hematopoiesis in collagen X null mice.

C J Gress O Jacenko

J Cell Biol 2000 May;149(4):983-93

University of Pennsylvania School of Veterinary Medicine, Department of Animal Biology, Philadelphia, PA 19104-6046, USA.

A variable skeleto-hematopoietic phenotype was observed in collagen X null mice which mirrored the defects in transgenic (Tg) mice with dominant interference collagen X mutations (Jacenko, O., P. LuValle, and B. Read More

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Activation of adenosine A2 alpha receptors inhibits mast cell degranulation and mast cell-dependent vasoconstriction.

Microcirculation 2000 Apr;7(2):129-35

Department of Cardiology, University of Virginia Health Sciences Center, Charlottesville, VA22906-0011, USA.

Objective: Adenosine and inosine accumulate in tissue during periods of ischemia and both molecules have been shown to degranulate mast cells in the hamster cheek pouch via activation of an A3 receptor. An A2-mediated inhibitory action of adenosine on mast cell degranulation has also been reported (16), and the objective of this research was to investigate the role of adenosine A2 receptors in modulating inosine-induced mast cell degranulation and subsequent vasoconstriction of microvessels.

Methods: Cheek pouches of the Golden hamster were prepared for in vivo microscopy. Read More

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Circumscribed lesion of the medial forebrain bundle area causes structural impairment of lymphoid organs and severe depression of immune function in rats.

Mol Psychiatry 1998 Sep;3(5):397-404

Clinical Neuroendocrinology Branch, National Institute of Mental Health, NIH, Bethesda, MD 20892-1284, USA.

Interactions between the immune system and the brain are a key element in the pathophysiology of diseases such as multiple sclerosis, neuroAIDS, and Alzheimer's, which affect large numbers of individuals and are associated with a high social cost. However, the neuroanatomical basis of brain-immune interactions has not been elucidated. We report that in Wistar rats of either sex bilateral electrolytic lesion of the medial forebrain bundle reduces body weight by 28% 7 days after lesioning, and causes widespread infections, aphagia, adypsia, structural damage to the lymphoid organs and heavy depression of T lymphocytes cytotoxicity. Read More

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September 1998

Alterations of the architecture of subendocardial arterioles in patients with hypertrophic cardiomyopathy and impaired coronary vasodilator reserve: a possible cause for myocardial ischemia.

J Am Coll Cardiol 1998 Apr;31(5):1089-96

Department of Cardiology, Pneumology and Angiology, Heinrich Heine University, Düsseldorf, Germany.

Objectives: The study was designed to investigate the architecture of subendocardial arterioles of patients with hypertrophic cardiomyopathy (HCM) and angina pectoris with respect to coronary vasodilator reserve.

Background: There is growing evidence that the coronary microvasculature is abnormal in HCM. Arterioles, which mainly regulate intramyocardial blood flow, are especially suspect. Read More

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Generation of the germline peripheral B cell repertoire: VH81X-lambda B cells are unable to complete all developmental programs.

J Immunol 1998 Apr;160(8):3748-58

Department of Microbiology, University of Alabama at Birmingham, 35394-3300, USA.

The generation of VH81X heavy chain lambda-light chain-expressing B cells (VH81X-lambda+ B cells) was studied in VH81X heavy chain transgenic mice as well as in VH81X JH (-/-) and VH81X JH (-/-) Ck (-/-) mice, in which competition resulting from expression of heavy and light chains from the endogenous heavy and kappa light chain loci was prevented. We show that although lambda light chain gene rearrangements occur normally and give rise to light chains that associate with the transgenic heavy chain to form surface and soluble IgM molecules, further B cell development is almost totally blocked. The few VH81X-lambda+ B cells that are generated progress into a mature compartment (expressing surface CD21, CD22, CD23, and low CD24 and having a relatively long life span) but they also have reduced levels of surface Ig receptor and express higher amounts of Fas Ag than VH81X-kappa+ B cells. Read More

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Structural analysis of arteriolar and myocardial remodelling in the subendocardial region of patients with hypertensive heart disease and hypertrophic cardiomyopathy.

Virchows Arch 1997 Oct;431(4):265-73

Department of Internal Medicine, Heinrich-Heine University of Düsseldorf, Germany.

Left ventricular hypertrophy is a risk factor for cardiovascular morbidity and mortality. In arterial hypertension and in hypertrophic cardiomyopathy it may be accompanied by clinical signs of myocardial ischaemia resulting from microcirculatory dysfunction in the absence of coronary macroangiopathy. Structural changes of the vascular and interstitial compartment of the heart are involved in the pathogenesis of impaired microcirculation. Read More

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October 1997

Quantitation of the changes in splenic architecture during the rejection of cardiac allografts or xenografts.

Transplantation 1997 Aug;64(3):448-53

Department of General Surgery, Rush Medical College and Rush Presbyterian St. Luke's Medical Center, Chicago, Illinois 60612, USA.

Background: The spleen plays a central role in the generation of both cellular and antibody responses during graft rejection. Although changes in lymphocyte function have been extensively analyzed in vitro, there have been limited attempts at quantitating the structural changes in the lymphoid compartments within the spleen during graft rejection.

Methods: We describe here a means of quantitating the histological changes in the spleen using immunohistochemical techniques and computerized image analysis. Read More

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Alterations in sympathetic innervation of thymus and spleen in aged mice.

Mech Ageing Dev 1997 Mar;94(1-3):165-75

Department of Neurobiology and Anatomy, University of Rochester School of Medicine and Dentistry, NY 14642, USA.

Age is associated with reduced immune reactivity, contributing to increased rates of infectious disease and cancer in old age. We have begun to assess the potential for sympathetic nervous system involvement in age-related immune dysfunction by characterizing sympathetic noradrenergic (NA) innervation in lymphoid organs in old animals. In the present study noradrenergic innervation of spleen and thymus was examined histologically and neurochemically in 2-, 12- and 24-month old BALB/c mice. Read More

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