39 results match your criteria fetuses grf


Influence of intrauterine growth status on aortic intima-media thickness and aortic diameter in near-term fetuses: a comparative cross-sectional study.

J Dev Orig Health Dis 2021 Jun 15:1-8. Epub 2021 Jun 15.

Maternal Fetal Medicine Unit, Department of Obstetrics and Gynaecology, Aga Khan University, Pakistan.

Intrauterine undernutrition may lead to fetal vascular programming. We compared abdominal aortic intima-media thickness (aIMT) and aortic diameter (aD) between appropriate for gestational age (AGA) and growth-restricted fetuses (GRF). We recruited 136 singleton fetuses at 34-37 weeks of gestation from Fetal Medicine Unit of Aga Khan University Hospital, Karachi (January-November 2017). Read More

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Early markers of endocrinometabolic disease in newborns with delayed intrauterine growth.

Clin Nutr ESPEN 2019 12 9;34:37-44. Epub 2019 Oct 9.

Hospital Universitario Clínico San Carlos, Madrid, Spain. Electronic address:

Introduction: The adjustments to malnutrition in growth restricted fetus (GRF) that lead to obesity, insulin resistance, diabetes and cardiovascular disease in adulthood are not well known. The most feasible explanation for this association is the hypothesis of catch up. Some studies postulate a greater influence of catch up growth than the low birth weight itself in developing metabolic and cardiovascular disease. Read More

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December 2019

Erythropoietin in amniotic fluid as a potential marker in distinction between growth restricted and constitutionally small fetuses.

J Matern Fetal Neonatal Med 2014 Jul 28;27(11):1134-7. Epub 2013 Oct 28.

Department of High-risk Pregnancies, University Clinic for Gynecology and Obstetrics "Narodni front", Medical School, University of Belgrade , Belgrade , Serbia .

Objective: To determine if there is any difference in amniotic fluid erythropoietin (EPO) concentration between fetuses small for gestational age (SGA) and appropriate for gestational age (AGA), and between the constitutionally small (CSF) and growth-restricted (GRF) fetuses.

Methods: EPO concentrations in the amniotic fluid samples were determined by EpoELISA test in 38 pregnancies with SGA and 15 pregnancies with AGA fetuses. In the SGA group we measured Ponderal index (PI) and skin-fold thickness (SFT). Read More

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Maternal undernutrition alters triiodothyronine concentrations and pituitary response to GnRH in fetal sheep.

J Endocrinol 2002 Jun;173(3):449-55

Macaulay Land Use Research Institute, Craigiebuckler, Aberdeen AB15 8QH, Scotland, UK.

The aims of this study were to determine which hormones may have a role in the expression of maternal undernutrition effects on reproductive function, in both the developing fetus and the adult offspring. This was undertaken by measuring the effects of long-term maternal undernutrition on metabolic hormone profiles and pituitary responses to single doses of GnRH and GH-releasing factor (GRF) in fetal sheep. From mating, groups of ewes were fed rations providing either 100% (HIGH) or 50% (LOW) of estimated metabolisable energy requirements for pregnancy throughout the experiment until slaughter at approximately 119 days of gestation. Read More

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[Prenatal diagnosis. I: Prenatal diagnosis program at the Medical Genetics Unit of the Universidad de Zulia, Maracaibo, Venezuela].

Invest Clin 1998 Jun;39(2):97-116

Unidad de Genetica Médica, Facultad de Medicina, Universidad del Zulia.

The Prenatal Diagnosis Program of the Medical Genetic Unit of University of Zulia has the following objectives: Identification of Genetic Risk Factors (GRF) in those couples who attend to the Prenatal Genetic Clinic, application of different prenatal diagnostic procedures (PDP), and providing adequate genetic counseling. The goal of this paper is to show preliminary results obtained between January 1993 and December 1996. Three hundred and twenty one pregnant women were analyzed by determining the GRF and taking into account the genetic clinical history. Read More

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Effect of fetal alcohol exposure on postnatal pituitary adenosine 3', 5'-cyclic phosphate content and growth hormone release.

Alcohol Clin Exp Res 1996 Oct;20(7):1212-20

Biology Department, Northern Illinois University, DeKalb 60115, USA.

This study examines the influence of fetal ethanol (ETOH) exposure and pair-feeding dams on postnatal, releasing factor-induced pituitary growth hormone (GH) release and adenosine 3',5'-cyclic phosphate (cAMP) accumulation. Fetuses were exposed to ETOH in utero by feeding dams a 36% (calories derived from ETOH: 6.6% v/v) ETOH liquid diet. Read More

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October 1996

Expression of alternative forms of Ras exchange factors GRF and SOS1 in different human tissues and cell lines.

Oncogene 1996 Mar;12(5):1097-107

Laboratory of Cellular and Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USA.

DNA probes and antibodies specific for different coding regions of human SOS1 and GRF genes were used to screen expression of these genes in a variety of adult and fetal human tissues and cell lines. Despite previous reports of the exclusive expression of hGRF RNA in brain, we also observed expression of this gene in various other tissues including lung and pancreas, as well as several tumor cell lines. At least three different hGRF mRNA transcripts were observed depending on the probe used, with the larger transcripts being detected by probes corresponding to the 5' end of the gene while smaller transcripts were detected by probes corresponding to the 3' end. Read More

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The fetal somatotropic axis during long term maternal undernutrition in sheep: evidence for nutritional regulation in utero.

Endocrinology 1995 Mar;136(3):1250-7

Department of Pediatrics, University of Auckland, New Zealand.

Nutrition is a major determinant of the somatotropic axis during postnatal life. However, little is known about the response of the fetal somatotropic axis to nutritional limitation. From day 100 of gestation (term = 147 days), singleton-bearing ewes were fed either ad libitum (control; n = 6) or 25% of the recommended energy and protein requirements (restricted; n = 7). Read More

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Biosynthesis of growth hormone-releasing factor by fetal rat cerebrocortical and hypothalamic cells.

Peptides 1994 ;15(5):825-8

Servicio de Endocrinología, Instituto de Salud Carlos III, Madrid, Spain.

The biosynthesis of growth hormone-releasing factor (GRF) by cerebrocortical tissue is controversial. Although several reports have indicated its presence in certain rat cortical areas and in cultured rat hypothalamic cells, no data exist demonstrating its biosynthesis in these areas. In this study, we have investigated the capacity of fetal rat cerebrocortical and hypothalamic cells in culture for synthesizing GRF. Read More

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January 1995

In vitro modulation of growth hormone (GH) secretion from early to midgestation human fetal pituitaries by GH-releasing factor and somatostatin: role of Gs-adenylate cyclase-Gi complex and Ca2+ channels.

J Clin Endocrinol Metab 1993 May;76(5):1265-70

McGill University-Montreal Children's Hospital Research Institute, McGill Centre for the Study of Reproduction, Quebec, Canada.

Using explant cultures of human fetal anterior pituitary glands (9-19 weeks fetal age) and an acute (3-h) test protocol, we investigated the role of two signal transduction pathways (Gs-adenylate cyclase-Gi, Ca2+ channels) in GH-releasing factor (GRF)/somatostatin (SRIF) regulation of GH secretion during the first half of gestation. Data have been analyzed for ontogenic changes using three age groups: 9-10, 12-13, and 15-19 weeks fetal age. The fetal somatotrope shows dose-related responses to forskolin (0. Read More

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Regulation of somatostatin and growth hormone-releasing factor by gonadal steroids in fetal rat hypothalamic cells in culture.

Regul Pept 1992 Dec;42(3):135-44

Servicio de Endocrinología, Hospital Ramón y Cajal, Madrid, Spain.

The mechanism underlying the sexually dimorphic pattern of growth hormone (GH) secretion in the rat has not been clearly elucidated. In the present study, we assayed the possible direct effect of gonadal steroids on both somatostatin (SS) and growth hormone-releasing factor (GRF) in fetal rat hypothalamic cells in culture. Hypothalamic cells, obtained by mechanical dispersion, were maintained as monolayer cultures in serum-supplemented medium. Read More

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December 1992

In vivo growth hormone (GH) response to human GH-releasing factor (GRF) or somatostatin (SRIF) in foetal pigs.

J Dev Physiol 1992 Feb;17(2):93-7

Agriculture Canada, Research Station, Lennoxville, Québec.

The short-term effect of hypothalamic GRF and SRIF on the pituitary release of GH at different stages of gestation has been studied. In the present experiment eighteen gilts were used, six at each of 66, 88 and 110 days of gestation. Ventral laparotomy was performed under general anaesthesia and a section of uterus was exteriorized. Read More

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February 1992

GRF treatment of late pregnant ewes alters maternal and fetal somatotropic axis activity.

Am J Physiol 1991 Apr;260(4 Pt 1):E575-80

Institut National de la Recherche Agronomique, Unité de Différenciation Cellulaire et Croissance, Montpellier, France.

To examine the effects of anabolic agents given during late gestation on the maternal and fetal somatotropic axes, we injected pregnant ewes twice daily with 0.15 mg somatocrinin (GRF)-(1-29) for 10 days beginning on day 130 of gestation. Maternal and fetal endocrine changes were compared with control animals using both in vivo and in vitro approaches. Read More

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Hormone ontogeny in the ovine fetus. XXV. Somatotrope desensitization to growth hormone releasing factor (GRF) independent of short-latency, ultrashortloop GH feedback.

Neuroendocrinology 1990 Nov;52(5):429-33

Department of Pediatrics, University of California, San Francisco.

Plasma ovine growth hormone (oGH) concentrations are strikingly elevated in the ovine fetus and decline at birth towards the low levels observed in the newborn lamb. We postulated that developmental changes in somatotrope function secondary to GH-releasing factor (GRF) desensitization and GH feedback play a role in the developmental pattern of oGH secretion and tested this hypothesis in vito in chronically catheterized ovine fetuses (123-145 days gestation; term 147 days) and newborn lambs (1-18 days). In the first set of studies, two consecutive intravenous GRF(1-44 amide) boluses (1 microgram/kg) were administered. Read More

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November 1990

Perinatal growth hormone (GH) physiology: effect of GH-releasing factor on maternal and fetal secretion of pituitary and placental GH.

J Clin Endocrinol Metab 1990 Aug;71(2):520-2

Department of Pediatrics, University Hospital Gasthuisberg, Leuven, Belgium.

To study regulation of the secretion of human pituitary GH (hGH) and placental GH (hPGH) in the pregnant woman and human fetus, the GH-releasing factor Sermorelin [GRF-(1-29)-NH2] was administered to pregnant women at term (n = 5), just before elective cesarean section; saline was administered in control studies (n = 5). The effects of GRF-(1-29)-NH2 administration on maternal and fetal serum concentrations of hGH and GRF-(1-29)-NH2 and maternal serum levels of hPGH were evaluated at birth. The mean time span between injection and birth was 20 min (range, 15-25 min). Read More

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Neurosecretory and trophic action on fetal rat neuroblasts induced by an amino acid mixture.

Biochem Med Metab Biol 1990 Feb;43(1):10-21

Servicio de Endocrinología, Hospital Ramón y Cajal, Madrid, Spain.

The effects of a synthetically obtained mixture of amino acids (FACE) were investigated on the trophic and neurosecretory activity of in vitro cultures of fetal rat neuronal cells. The addition of 10(-6) M FACE to the culture medium significantly increased cell DNA content. Secretions of IR-SRIF, IR-VIP, and IR-GRF were also augmented in different proportions by the presence of FACE. Read More

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February 1990

Growth hormone-releasing factor production by fetal rat cerebrocortical and hypothalamic cells in primary culture.

Endocrinology 1989 Oct;125(4):1991-8

Servicio de Endocrinología, Hospital Ramón y Cajal, Madrid, Spain.

Recent data from our laboratory and others have shown radioimmunoassayable GRF (IR-GRF) in the rat brain cortex. In the present study the ontogenesis of immunoreactive rat(r) GRF (IR-GRF) in long term dissociated fetal rat cerebrocortical and hypothalamic cell cultures and the regulation of its secretion by potassium depolarization and calcium channel-blocking agents were investigated. The chromatographic profiles of IR-rGRF from cell extracts were determined and compared with those from in vivo cerebrocortical and hypothalamic tissues. Read More

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October 1989

Synthesis and secretion of vasoactive intestinal peptide by rat fetal cerebral cortical and hypothalamic cells in culture.

Endocrinology 1989 Oct;125(4):1983-90

Servicio de Endocrinologia, Hospital Ramón y Cajal, Madrid, Spain.

To establish the neurosecretory activity of brain vasoactive intestinal peptide (VIP)ergic neurons and to characterize the molecular forms of secretion of these cells, fetal cerebrocortical and hypothalamic cells were grown in primary cultures for periods up to 4 weeks, their regulation by depolarization and calcium and sodium channel active agents was studied, and the chromatographic patterns of cell and medium VIP were determined. Mechanically dispersed cultured fetal telencephalic and diencephalic cells showed a progressive increase in immunoreactive VIP in both cells and media, reaching maximum values between 110-290 pg/mg protein.culture plate on days 15-20. Read More

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October 1989

Sex-specific effects on the fetal neuroendocrine system during acute stress in late pregnancy of rat and the influence of a simultaneous treatment by tyrosine.

Exp Clin Endocrinol 1989 Sep;94(1-2):23-42

Institute of Experimental Endocrinology, Humboldt University School of Medicine, Berlin, GDR.

It is well-known that prenatal chronic intermittent stress affects the reproductive system of both sexes. Investigating the effects of an acute maternal stress on the fetal neuroendocrine system, parameters such as hypothalamic catecholamines. CRF, GRF, LH-RH, beta-endorphin, hypophysial beta-endorphin and beta-LPH as well as plasma LH, corticosterone and androstenedione were measured. Read More

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September 1989

Hormone ontogeny in the ovine fetus and neonate. XXII. The effect of somatostatin on the growth hormone (GH) response to GH-releasing factor.

Endocrinology 1989 Mar;124(3):1114-7

Department of Pediatrics, University of California, San Francisco 94143.

We postulated that an increase in the biological effectiveness of somatostatin (SRIF) accounts, at least in part, for the decrease in basal and GRF-induced ovine GH (oGH) secretion observed around birth in the ovine fetus and neonate. To test this hypothesis, SRIF (SRIF-14; given as 30 micrograms/kg iv bolus, followed by 2 micrograms/kg.min for 75 min) was infused into chronically catheterized fetal and neonatal lambs, and the oGH response induced by GRF [GRF-(1-44) amide; 1 microgram/kg] in the presence of exogenous SRIF was compared to the oGH response induced by GRF in saline-infused controls. Read More

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Regulation of growth hormone (GH) secretion by GH-releasing factor, somatostatin, and insulin-like growth factor I in ovine fetal and neonatal pituitary cells in vitro.

Endocrinology 1989 Jan;124(1):84-9

Department of Pediatrics, University of California, San Francisco 94143.

Serum GH concentrations in the ovine fetus are much higher than those in the neonate, and the maximal GH response induced by GRF is 5-fold greater in the fetus than in the neonate. To clarify these in vivo observations further, we studied the effects of GRF, somatostatin (SRIF), and insulin-like growth factor I (IGF-I) on primary cultures of fetal and neonatal ovine pituitary cells. GH secretion from fetal ovine pituitary cells increased from 148 +/- 34 to 950 +/- 130 ng/10(5) cells. Read More

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January 1989

Hormone ontogeny in the ovine fetus and neonatal lamb. XX. Effect of age, breeding season, and twinning on the growth hormone (GH) response to GH-releasing factor: evidence for a homeostatic role of fetal GH.

Endocrinology 1989 Jan;124(1):124-8

Department of Pediatrics, University of California, San Francisco 94143-0106.

The ovine GH (oGH) response to GRF (1-44 amide) was evaluated in 74 chronically catheterized fetal and neonatal lambs. After a 1-h control period, GRF was administered iv, and the oGH response was studied during the next 60 min. The following variables were analyzed: GRF dose, fetal or neonatal age, breeding season, and singleton or multiple pregnancy. Read More

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January 1989

In vitro regulation of growth hormone (GH) release from ovine pituitary cells during fetal and neonatal development: effects of GH-releasing factor, somatostatin, and insulin-like growth factor I.

Endocrinology 1988 May;122(5):2114-20

Station de Physiologie Animale, INRA-ENSA, Montpellier, France.

Using a monolayer approach, we have examined the acute (3 h) effects of GRF, somatostatin (SRIF), and insulin-like growth factor I (IGF-I) on GH release from pituitary cells of male and female 70-, 100-, and 130-day-old fetuses and newborn lambs and of prepubertal male lambs. GRF stimulated basal GH release in a dose-dependent (10(-12)-10(-8) M) manner at each stage in development. There was no linear relationship between maximal response and increasing age of the donor animals. Read More

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The effect of an acute maternal stress on beta-endorphin and growth hormone releasing factor in the rat fetus.

Exp Clin Endocrinol 1988 Mar;91(1):35-42

Department of Obstetrics and Gynecology, Teikyo University, School of Medicine, Japan.

Pregnant rats were injected with saline or L-tyrosine methylester HCl (200 mg/kg) and subjected to an acute forced immobilization stress on day 20 of gestation. At 10, 30, 60, and 120 minutes after the onset of stress, their fetuses were dissected out, and the contents of hypothalamic and pituitary immunoreactive beta-endorphin (IR-beta-EP) and hypothalamic immunoreactive growth hormone-releasing factor (IR-GRF) were determined by specific radioimmunoassays. The maternal stress arose a significant decrease of hypothalamic IR-beta-EP at 30 minutes, while pituitary IR-beta-EP slightly elevated at 30 minutes, then declined at 60 minutes. Read More

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Regulation of growth hormone release in fetal calves.

Biol Neonate 1988 ;54(3):160-8

UA CNRS, Inra Theix, Ceyrat, France.

Plasma GH and IGF1 concentrations were measured during the last 2 months of gestation in 9 chronically catheterized fetal calves under basal conditions or following growth-hormone-releasing factor (GRF), thyrotropin-releasing hormone (TRH) or SRIF intravenous cotyledonnary injections. Plasma GH concentrations were higher in fetuses (1.40 +/- 0. Read More

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Structural specificity of peptides influencing neuronal survival during development.

Peptides 1987 Jul-Aug;8(4):687-94

Vasoactive intestinal peptide (VIP) has been shown to increase the survival of developing neurons grown in dissociated spinal cord cultures. This result was evident when synaptic activity was blocked with tetrodotoxin (TTX) during a critical period of development (days 7-21 after plating). Other neuropeptides, with a close sequence homology to VIP, have now been tested for their effects on neuronal survival in culture. Read More

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October 1987

Pre- and postnatal developmental changes in hypothalamic content of rat growth hormone-releasing factor.

Endocrinology 1987 Feb;120(2):525-30

The ontogenesis of hypothalamic GH-releasing factor (GRF) in pre- and postnatal rats was examined by means of a specific rat GRF RIA. Whereas GRF content was undetectable (less than 10 pg/hypothalamus) on day 17 of gestation, it increased to 30-65 pg/hypothalamus during days 18-20. During postnatal life, hypothalamic GRF content increased more rapidly during days 20-50 than during days 0-20 or 50-90. Read More

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February 1987

Influence of endogenous growth hormone-releasing factor (GRF) on the secretion of GH during the perinatal period in the rat.

Peptides 1986 May-Jun;7(3):393-6

Passive immunization of pregnant rats with a specific antiserum to rat GRF (GRF-AS) is followed by a decrease in fetal serum GH on the 19th day of gestation. A significant reduction in serum GH is still observed in older fetuses and newborn rats. Pituitary GH content increases in 19- and 20-day-old fetuses after GRF-AS administration to their mothers. Read More

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December 1986

Ontogeny of growth hormone-releasing factor in the rat hypothalamus.

Neuroendocrinology 1986 ;44(1):59-64

Using immunohistochemical techniques, we have studied the ontogenetic development of growth hormone-releasing factor (GRF) immunoreactive structures in the rat hypothalamus. Frozen sections of rat hypothalami were stained by the avidin-biotin complex (ABC) method using a specific antiserum against rat GRF. Immunoreactive GRF nerve terminals but not perikarya were first detected in rat fetuses on the 20th day of gestation in the external layer of the median eminence (ME). Read More

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January 1987

[Ontogenesis in man, of a population of neurons in the dorsal and lateral hypothalamus, secretors of a peptide that has not yet been characterized].

C R Seances Soc Biol Fil 1986 ;180(2):175-83

A human GRF 1-37 antiserum demonstrates a new neuronal system in lateral perifornical areas of the human hypothalamus. The molecule that is revealed in those neurons cannot be somatocrinin. Perikarya are abundant. Read More

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January 1987