Hypothalamic gonadotropin-releasing hormone receptor activation stimulates oxytocin release from the rat hypothalamo-neurohypophysial system while melatonin inhibits this process

  title={Hypothalamic gonadotropin-releasing hormone receptor activation stimulates oxytocin release from the rat hypothalamo-neurohypophysial system while melatonin inhibits this process},
  author={Marlena Juszczak and Emilia Boczek-Leszczyk},
  journal={Brain Research Bulletin},
The present study was undertaken to investigate the influence of gonadotropin-releasing hormone (GnRH) and its agonist and antagonist on oxytocin (OT) release from the rat hypothalamo-neurohypophysial (H-N) system. An additional aim was to determine whether the possible response of oxytocinergic neurons to these peptides could be modified by melatonin through a cAMP-dependent mechanism. The results show that the highly selective GnRH agonist (i.e., [Des-Gly(10),d-His(Bzl)(6),Pro-NHEt(9)]-LHRH… Expand
Oxytocin and vasopressin secretion from the rat hypothalamo-neurohypophysial system is stimulated by triptorelin.
Triptorelin may play a role as a neuromodulator contributing to the functional regulation of OT and AVP secretion in the rat. Expand
The role of melatonin membrane receptors in melatonin-dependent oxytocin secretion from the rat hypothalamo-neurohypophysial system - an in vitro and in vivo approach.
The present study demonstrates that an inhibitory effect of 10-7 M melatonin on oxytocin secretion from the rat H-N system is mediated through a subtype MT1 membrane receptor and its action is independent of sub type MT2 receptor. Expand
More than reproduction: Central gonadotropin‐releasing hormone antagonism decreases maternal aggression in lactating rats
Investigating the effects of acute central GnRH receptor blockade in lactating rats on maternal care under non‐stress and stress conditions, maternal motivation in the pup retrieval test, maternal anxiety on the elevated plus maze, and maternal aggression in the maternal defence test shed new light on GnRH as a neuropeptide acting not exclusively on the reproductive axis but, additionally, on maternal behaviour including pup retrieval and maternal aggressive behaviour. Expand
Effect of combined lignan phytoestrogen and melatonin treatment on secretion of steroid hormones by adrenal carcinoma cells.
The concept that this combination of lignan and melatonin may yield similar effects on steroid hormone secretion by the adrenal glands in dogs with typical and atypical hyperadrenocorticism is supported. Expand
Postpartum depression: psychoneuroimmunological underpinnings and treatment
The biological underpinnings to PPD are reviewed, suggesting a powerful role for the tryptophan catabolites, indoleamine 2,3-dixoygenase, serotonin, and autoimmunity in mediating the consequences of immuno-inflammation and oxidative and nitrosative stress. Expand
Seasonal and Sex Differences in the Effects of Melatonin on Brain Arginine Vasotocin in Green Treefrogs (Hyla cinerea): Relationship to Melatonin Receptor 1a
This Thesis aims to explore the relationship between seasonal and sex differences in the effects of Melatonin on Brain Arginine Vasotocin in Green Treefrogs (Hyla cinerea) and its relationship to Melatonin Receptor 1a. Expand


Gonadotrophin-releasing hormone and oxytocin secretion from the hypothalamus in vitro during pro-oestrus: the effects of time of day and melatonin
It is observed that secretion from the hypothalamus of the two LH-regulating peptides, GnRH and oxytocin, are differently regulated during the day of pro-oestrus, and melatonin was observed to inhibit basal Oxytocin secretion from hypothalami collected during light hours. Expand
Diurnal modulation of rat hypothalamic gonadotropin-releasing hormone release by melatonin in vitro
  • D. Rasmussen
  • Biology, Medicine
  • Journal of endocrinological investigation
  • 1993
The results suggest that there are clearly diurnal mechanisms within the male rat hypothalamus by which MEL can either facilitate or suppress GnRH release. Expand
Hypothalamic control of gonadotropin secretion by LHRH, FSHRF, NO, cytokines, and leptin.
An exciting recent development has been the discovery of the adipocyte hormone, leptin, a cytokine related to tumor necrosis factor (TNF) alpha that may play an important role in induction of puberty and control of LHRH release in the adult as well. Expand
Presence of Oxytocin Receptors in the Gonadotrophin‐Releasing Hormone (GnRH) Neurones in Female Rats: A Possible Direct Action of Oxytocin on GnRH Neurones
Oxytocin may directly control neuronal activity in a subpopulation of GnRH neurones in the medial preoptic area of the rat, suggesting an oxytocin central action during the oestrous cycle. Expand
Role of tachykinin receptors and melatonin in oxitocin secretion from isolated rat hypothalmo-neurohypophysial system.
A distinct role for tachykinin NK-1 (rather than NK-2) receptor in tachyKinin-mediated regulation of OT secretion from the rat H-N system is indicated and under present experimental conditions, however, a role of respective tachy Kinin receptors in the response of oxytocinergic neurons to melatonin has not been found. Expand
Mechanisms of Melatonin Inhibition of Neurohypophysial Hormone Release From the Rat Hypothalamus In Vitro
It is suggested that melatonin may influence neurohypophysial hormone release through modulation of afferent pathways mediated by acetylcholine, dopamine, and/or prostaglandin. Expand
Melatonin and its analogs inhibit the basal and stimulated release of hypothalamic vasopressin and oxytocin in vitro.
It is suggested that circadian rhythmicity in pituitary-adrenal activity may depend on melatonin modulation of AVP, rather than changes in CRH-41, and that melatonin may affect water balance by means of directly inhibiting hypothalamic AVP release. Expand
Gonadotropin-releasing hormone neurons in the preoptic-hypothalamic region of the rat contain lamprey gonadotropin-releasing hormone III, mammalian luteinizing hormone-releasing hormone, or both peptides
L-GnRH-III neurons not only are observed in regions that control follicle-stimulating hormone release but also are colocalized with m-LHRH neurons in areas primarily controlling LH release, suggesting an interrelationship between these two peptides in the control of gonadotropin secretion. Expand
Luteinizing hormone-releasing hormone and oxytocin response to hyperosmotic stimulation: in vitro study
It is concluded that LHRH may participate in the regulation of oxytocin secretion via both direct and indirect impact on magnocellular Oxytocinergic neurones depending on the current functional status of the hypothalamo-neurohypophysial complex. Expand
Neurokinin A and the neurohypophysial response to melatonin: in vitro studies.
  • M. Juszczak
  • Medicine, Biology
  • Journal of physiology and pharmacology : an official journal of the Polish Physiological Society
  • 2002
The present results confirm previous reports as to the inhibitory effect of melatonin on both vasopressin and oxytocin secretion from the hypothalamo-neurohypophysial complex in vitro. Expand