Consulta: subjectFacets:"Oxytocin"
Registros recuperados: 17
Data/hora: 10/06/2024 06:32:38

Relationship between Peripartal Plasma Oxytocin and Prostaglandin F2α Metabolite and Placental Expulsion Time in Heavy Draft Mares
Provedor de dados: Obihiro University of Agriculture and Veterinary Medicine Academic Repository (OAK)
Autores: ISHII, Mitsuo; KOBAYASHI, Syuichi; ACOSTA, Tomas J.; MIKI, Wataru; YAMANOI, Takahiro; MATSUI, Motozumi; MIYAKE, Yoh-Ichi; MIYAMOTO, Akio; 石井, 三都夫; 松井, 基純; 三宅, 陽一; 宮本, 明夫.
The aim of this study was to clarify the relationship between circulating oxytocin (OT) and PGF2α metabolite (PGFM) in mares at the third stage of labor and placental expulsion time in order to investigate a cause of retained placenta of which the incidence increase in a heavy draft mare. Blood was sampled every 5 min from foaling to expulsion of the placenta in 18 heavy draft mares to evaluate circulating OT and PGFM. The relationships between OT and PGFM concentration and recorded placental expulsion times were investigated. The results were as follows (1) The highest level of OT concentration was observed close to foaling in 15 mares. (2) The OT concentrations close to foaling were variable with a large difference from the lowest concentration, 22.1...
Palavras-chave: Heavy draft mare; Oxytocin; 15-keto-dihydro prostaglandin F2α (PGFM); Placental expulsion.
Ano: 2008
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/3089

Cervical relaxation for non-surgical uterus access in Santa Inês ewes
Provedor de dados: Arquivo Brasileiro de Medicina Veterinária e Zootecnia
Autores: Leite,C.R.; Fonseca,J.F.; Fernandes,D.A.M.; Souza-Fabjan,J.M.G.; Ascoli,F.O.; Brandão,F.Z.
ABSTRACT The present study was composed by two experiments aiming to develop a cervical dilation technique for non-surgical access to Santa Inês ewe’s uterus. In Experiment 1, thirty ewes underwent four epidural treatments. The three experimental treatments used 2.0mg/kg ketamine. The group receiving this drug alone was denominated KG, whereas other group had ketamine associated with 0.1mg/kg morphine (KM) and KX a third group had ketamine associated with 0.05mg/kg xylazine (KX). Control treatment was 1mL/7.5kg saline solution epidurally (CON). Cervical dilation was evaluated in both experiments by attempting to pass a metal rod through the cervix. In Experiment 2, three different hormonal protocols for cervical dilation were tested in thirty ewes....
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Epidural ketamine; Estradiol; Misoprostol; Oxytocin; Sheep cervix.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-09352018000601671

Social stimuli cause changes of plasma oxytocin and behavior in guinea pigs
Provedor de dados: Biological Research
Autores: WALLNER,BERNARD; DITTAMI,JOHN; MACHATSCHKE,IVO.
The neuropeptide oxytocin (OXT) is a key factor in the initiation and regulation of sociosexual behavior. The present study analyzes the effects of cohabitation and social challenge on plasma OXT concentration rates in guinea pig pairs in relation to male sociosexual behavior. The cohabitation phase lasted 3 days. On day 4, the pair was socially challenged by introducing an unfamiliar male. Displayed male sexual behavior varied significantly during cohabitation, with peaks on day 1. Sociopositive behavior, i.e., side-by-side contact, was increased on days 3 and 4. Cohabitation per se led to elevated plasma OXT concentrations only in males. In contrast, both sexes reacted with increased plasma OXT concentrations to the social challenge (day 4). At that...
Tipo: Journal article
Palavras-chave: Oxytocin; Behavior guinea pig social challenge cohabitation.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602006000200007

Influence of time at which oxytocin is administered during labor on uterine activity and perinatal death in pigs
Provedor de dados: Biological Research
Autores: MOTA-ROJAS,DANIEL; VILLANUEVA-GARCÍA,DINA; VELAZQUEZ-ARMENTA,ELVIA Y; NAVA-OCAMPO,ALEJANDRO A; RAMÍREZ-NECOECHEA,RAMIRO; ALONSO-SPILSBURY,MARÍA; TRUJILLO,MARÍA E.
Oxytocin is extensively used to induce or augment uterine contractions, especially to facilitate the third stage of labor in humans. Administration of oxytocin to parturient sows reduces duration of labor whereas mortality of the offspring may remain unchanged. This study aimed to evaluate whether time of administration of oxytocin during parturition may alter the uterine response and fetal outcomes. Two hundred parturient sows were randomly assigned to intramuscularly receive either saline solution (control group) or oxytocin 0.083 IU/kg immediately after the delivery of the 1st, 4th or 8th piglet (groups O-1, 0-4 and 0-8, respectively). Uterine effects and fetal outcomes were registered in all groups. The duration of labor was 20-40 min shorter (P &lt;...
Tipo: Journal article
Palavras-chave: Fetal distress; Fetal monitoring; Obstetric labor; Oxytocin; Uterine contractions.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602007000100006

Effects of nitric oxide on magnocellular neurons of the supraoptic nucleus involve multiple mechanisms
Provedor de dados: Brazilian Journal of Medical and Biological Research
Autores: Silva,M.P. da; Cedraz-Mercez,P.L.; Varanda,W.A.
Physiological evidence indicates that the supraoptic nucleus (SON) is an important region for integrating information related to homeostasis of body fluids. Located bilaterally to the optic chiasm, this nucleus is composed of magnocellular neurosecretory cells (MNCs) responsible for the synthesis and release of vasopressin and oxytocin to the neurohypophysis. At the cellular level, the control of vasopressin and oxytocin release is directly linked to the firing frequency of MNCs. In general, we can say that the excitability of these cells can be controlled via two distinct mechanisms: 1) the intrinsic membrane properties of the MNCs themselves and 2) synaptic input from circumventricular organs that contain osmosensitive neurons. It has also been...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Magnocellular neurons; Supraoptic nucleus; Vasopressin; Oxytocin; Nitric oxide; Homeostasis.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2014000200090

The role of oxytocin in cardiovascular regulation
Provedor de dados: Brazilian Journal of Medical and Biological Research
Autores: Gutkowska,J.; Jankowski,M.; Antunes-Rodrigues,J.
Studies of body volume expansion have indicated that lesions of the anteroventral third ventricle and median eminence block the release of atrial natriuretic peptide (ANP) into the circulation. Detailed analysis of the lesions showed that activation of oxytocin (OT)-ergic neurons is responsible for ANP release, and it has become clear that activation of neuronal circuitry elicits OT secretion into the circulation, activating atrial OT receptors and ANP release from the heart. Subsequently, we have uncovered the entire functional OT system in the rat and the human heart. An abundance of OT has been observed in the early development of the fetal heart, and the capacity of OT to generate cardiomyocytes (CMs) has been demonstrated in various types of stem...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Oxytocin; Natriuretic peptides; Heart; Cardiomyogenesis.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2014000300206

Nitric oxide modulation of the hypothalamo-neurohypophyseal system
Provedor de dados: Brazilian Journal of Medical and Biological Research
Autores: Kadekaro,M.
Nitric oxide (NO), a free radical gas produced endogenously from the amino acid L-arginine by NO synthase (NOS), has important functions in modulating vasopressin and oxytocin secretion from the hypothalamo-neurohypophyseal system. NO production is stimulated during increased functional activity of magnocellular neurons, in parallel with plastic changes of the supraoptic nucleus (SON) and paraventricular nucleus. Electrophysiological data recorded from the SON of hypothalamic slices indicate that NO inhibits firing of phasic and non-phasic neurons, while L-NAME, an NOS inhibitor, increases their activity. Results from measurement of neurohypophyseal hormones are more variable. Overall, however, it appears that NO, tonically produced in the forebrain,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: L-NAME; Vasopressin; Oxytocin; CGMP; ODQ; Microdialysis.
Ano: 2004
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2004000400001

Neuropeptides in the posterodorsal medial amygdala modulate central cardiovascular reflex responses in awake male rats
Provedor de dados: Brazilian Journal of Medical and Biological Research
Autores: Quagliotto,E.; Casali,K.R.; Dal Lago,P.; Rasia-Filho,A.A.
The rat posterodorsal medial amygdala (MePD) links emotionally charged sensory stimuli to social behavior, and is part of the supramedullary control of the cardiovascular system. We studied the effects of microinjections of neuroactive peptides markedly found in the MePD, namely oxytocin (OT, 10 ng and 25 pg; n=6/group), somatostatin (SST, 1 and 0.05 μM; n=8 and 5, respectively), and angiotensin II (Ang II, 50 pmol and 50 fmol; n=7/group), on basal cardiovascular activity and on baroreflex- and chemoreflex-mediated responses in awake adult male rats. Power spectral and symbolic analyses were applied to pulse interval and systolic arterial pressure series to identify centrally mediated sympathetic/parasympathetic components in the heart rate variability...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Baroreceptor and chemoreceptor reflexes; Power spectral analysis; Symbolic analysis; Oxytocin; Somatostatin; Angiotensin II.
Ano: 2015
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2015000200128

Gene expression of estrogen and oxytocin receptors in the uterus of pregnant and parturient bitches
Provedor de dados: Brazilian Journal of Medical and Biological Research
Autores: Veiga,G.A.L.; Milazzotto,M.P.; Nichi,M.; Lúcio,C.F.; Silva,L.C.G.; Angrimani,D.S.R.; Vannucchi,C.I.
In the canine species, the precise mechanisms of pregnancy maintenance and the initiation of parturition are not completely understood. The expression of genes encoding the receptors for estrogen (ERα mRNA) and oxytocin (OTR mRNA) was studied in the endometrium and myometrium during pregnancy and parturition in dogs. Real-time PCR was performed to quantify the levels of ERα mRNA and OTR mRNA in the uterus of bitches during early (up to 20 days of gestation), mid (20 to 40 days) and late pregnancy (41 to 60 days), and parturition (first stage of labor). All tissues expressed ERα and OTR mRNA, and are thus possibly able to respond to eventual estrogen and oxytocin hormonal stimuli. No statistically significant differences in the expression of ERα mRNA were...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Canine; Estrogen; Oxytocin; Receptors; Pregnancy; Parturition.
Ano: 2015
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2015000400339

Changes in the electrophysiological parameters of the posterior intestine of Anguilla anguilla (Pisces) induced by oxytocin, urotensin II and aldosterone
Provedor de dados: Brazilian Journal of Medical and Biological Research
In view of the importance of the intestine in the osmoregulation of freshwater fishes, we determined the effects of oxytocin, urotensin II (UII), and aldosterone added to the serosal side of the isolated posterior intestine of the freshwater-adapted teleost Anguilla anguilla on electrophysiological parameters. Oxytocin decreased the short-circuit current (SCC) and transepithelial potential difference (TPD) at concentrations of 1 and 10 mU/ml (to 50% and 42% of control values, respectively), but did not alter these parameters at a concentration of 0.1 mU/ml. UII reduced SCC and TPD at concentrations of 10 nM, 50 nM and 100 nM (to 85% of control values), but increased these parameters at the concentration of 500 nM (to 115% of control values). Aldosterone...
Palavras-chave: Intestine; Anguilla anguilla; Oxytocin; Urotensin II; Aldosterone.
Ano: 1997
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X1997000100006

Nitrergic modulation of vasopressin, oxytocin and atrial natriuretic peptide secretion in response to sodium intake and hypertonic blood volume expansion
Provedor de dados: Brazilian Journal of Medical and Biological Research
Autores: Ventura,R.R.; Gomes,D.A.; Reis,W.L.; Elias,L.L.K.; Castro,M.; Valença,M.M.; Carnio,E.C.; Rettori,V.; McCann,S.M.; Antunes-Rodrigues,J.
The central nervous system plays an important role in the control of renal sodium excretion. We present here a brief review of physiologic regulation of hydromineral balance and discuss recent results from our laboratory that focus on the participation of nitrergic, vasopressinergic, and oxytocinergic systems in the regulation of water and sodium excretion under different salt intake and hypertonic blood volume expansion (BVE) conditions. High sodium intake induced a significant increase in nitric oxide synthase (NOS) activity in the medial basal hypothalamus and neural lobe, while a low sodium diet decreased NOS activity in the neural lobe, suggesting that central NOS is involved in the control of sodium balance. An increase in plasma concentrations in...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Vasopressin; Oxytocin; ANP; Nitric oxide; Blood volume expansion; Sodium diet.
Ano: 2002
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2002000900011

Role of the hypothalamic pituitary adrenal axis in the control of the response to stress and infection
Provedor de dados: Brazilian Journal of Medical and Biological Research
Autores: McCann,S.M.; Antunes-Rodrigues,J.; Franci,C.R.; Anselmo-Franci,J.A.; Karanth,S.; Rettori,V.
The release of adrenocorticotropin (ACTH) from the corticotrophs is controlled principally by vasopressin and corticotropin-releasing hormone (CRH). Oxytocin may augment the release of ACTH under certain conditions, whereas atrial natriuretic peptide acts as a corticotropin release-inhibiting factor to inhibit ACTH release by direct action on the pituitary. Glucocorticoids act on their receptors within the hypothalamus and anterior pituitary gland to suppress the release of vasopressin and CRH and the release of ACTH in response to these neuropeptides. CRH neurons in the paraventricular nucleus also project to the cerebral cortex and subcortical regions and to the locus ceruleus (LC) in the brain stem. Cortical influences via the limbic system and possibly...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Corticotropin-releasing hormone (CRH); Vasopressin; Oxytocin; Atrial natriuretic peptide (ANP); ACTH; Cortisol; Norepinephrine; Acetyl choline; Nitric oxide.
Ano: 2000
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2000001000001

Oxytocin is a cardiovascular hormone
Provedor de dados: Brazilian Journal of Medical and Biological Research
Autores: Gutkowska,J.; Jankowski,M.; Mukaddam-Daher,S.; McCann,S.M.
Oxytocin (OT), a nonapeptide, was the first hormone to have its biological activities established and chemical structure determined. It was believed that OT is released from hypothalamic nerve terminals of the posterior hypophysis into the circulation where it stimulates uterine contractions during parturition, and milk ejection during lactation. However, equivalent concentrations of OT were found in the male hypophysis, and similar stimuli of OT release were determined for both sexes, suggesting other physiological functions. Indeed, recent studies indicate that OT is involved in cognition, tolerance, adaptation and complex sexual and maternal behaviour, as well as in the regulation of cardiovascular functions. It has long been known that OT induces...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Oxytocin; Natriuretic peptides; Heart.
Ano: 2000
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2000000600003

Central actions of glucocorticoids in the control of body fluid homeostasis: Review
Provedor de dados: Brazilian Journal of Medical and Biological Research
Autores: Ruginsk,S.G.; Lopes da Silva,A.; Ventura,R.R.; Elias,L.L.K.; Antunes-Rodrigues,J.
The involvement of the hypothalamic-pituitary-adrenal axis in the control of body fluid homeostasis has been extensively investigated in the past few years. In the present study, we reviewed the recent results obtained using different approaches to investigate the effects of glucocorticoids on the mechanisms of oxytocin and vasopressin synthesis and secretion in response to acute and chronic plasma volume and osmolality changes. The data presented here suggest that glucocorticoids are not only involved in the mechanisms underlying the fast release but also in the transcriptional events that lead to decreased synthesis and secretion of these neuropeptides, particularly oxytocin, under diverse experimental conditions of altered fluid volume and tonicity. The...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Corticosterone; Vasopressin; Oxytocin; Endocannabinoid; Glutamate; NFκB.
Ano: 2009
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2009000100010

GABA in the central amygdaloid nucleus modulates the electrolyte excretion and hormonal responses to blood volume expansion in rats
Provedor de dados: Brazilian Journal of Medical and Biological Research
Autores: Margatho,L.O.; Elias,L.L.K.; Antunes-Rodrigues,J.
We investigated the involvement of GABAergic mechanisms of the central amygdaloid nucleus (CeA) in unanesthetized rats subjected to acute isotonic or hypertonic blood volume expansion (BVE). Male Wistar rats bearing cannulas unilaterally implanted in the CeA were treated with vehicle, muscimol (0.2 nmol/0.2 µL) or bicuculline (1.6 nmol/0.2 µL) in the CeA, followed by isotonic or hypertonic BVE (0.15 or 0.3 M NaCl, 2 mL/100 g body weight over 1 min). The vehicle-treated group showed an increase in sodium excretion, urinary volume, plasma oxytocin (OT), and atrial natriuretic peptide (ANP) levels compared to control rats. Muscimol reduced the effects of BVE on sodium excretion (isotonic: 2.4 ± 0.3 vs vehicle: 4.8 ± 0.2 and hypertonic: 4.0 ± 0.7 vs vehicle:...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Central amygdaloid nucleus; Natriuresis; Urine output; Oxytocin; Atrial natriuretic peptide.
Ano: 2009
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2009000100016

Neuroendocrine regulation of salt and water metabolism
Provedor de dados: Brazilian Journal of Medical and Biological Research
Neurons which release atrial natriuretic peptide (ANPergic neurons) have their cell bodies in the paraventricular nucleus and in a region extending rostrally and ventrally to the anteroventral third ventricular (AV3V) region with axons which project to the median eminence and neural lobe of the pituitary gland. These neurons act to inhibit water and salt intake by blocking the action of angiotensin II. They also act, after their release into hypophyseal portal vessels, to inhibit stress-induced ACTH release, to augment prolactin release, and to inhibit the release of LHRH and growth hormone-releasing hormone. Stimulation of neurons in the AV3V region causes natriuresis and an increase in circulating ANP, whereas lesions in the AV3V region and caudally in...
Tipo: Info:eu-repo/semantics/other
Palavras-chave: Anteroventral third ventricle (AV3V) region; Blood volume expansion; ANP neurons; Oxytocin; Vasopressin; Plasma ANP; Thirst; Salt intake; Natriuresis; Kaliuresis.
Ano: 1997
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X1997000400001

Neuroendocrine control of body fluid homeostasis
Provedor de dados: Brazilian Journal of Medical and Biological Research
Autores: McCann,S.M.; Gutkowska,J.; Antunes-Rodrigues,J.
Angiotensin II and atrial natriuretic peptide (ANP) play important and opposite roles in the control of water and salt intake, with angiotensin II promoting the intake of both and ANP inhibiting the intake of both. Following blood volume expansion, baroreceptor input to the brainstem induces the release of ANP within the hypothalamus that releases oxytocin (OT) that acts on its receptors in the heart to cause the release of ANP. ANP activates guanylyl cyclase that converts guanosine triphosphate into cyclic guanosine monophosphate (cGMP). cGMP activates protein kinase G that reduces heart rate and force of contraction, decreasing cardiac output. ANP acts similarly to induce vasodilation. The intrinsic OT system in the heart and vascular system augments the...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Oxytocin; Vasopressin; Atrial natriuretic peptide; Nitric oxide; Angiotensin II; Guanylyl cyclase.
Ano: 2003
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2003000200003