Glucocorticoids are widely used in medical practice mainly for suppression of the immune system. According to Selye - who named them - the endogenous molecules are very important for the adaptation to challenges, stress. They were synthesized in the 1940s.
View Article and Find Full Text PDFThe nonapeptide arginine vasopressin (AVP) has long been suggested to play an important role as a secretagogue for triggering the activity of the endocrine stress response. Most recent studies employed mutant mice for analyzing the importance of AVP for endocrine regulation under stress. However, it is difficult to compare and draw overall conclusions from all these studies as mixing the genetic material from different mouse strains has consequences on the individual's stress response.
View Article and Find Full Text PDFEarly life events have special importance in the development as postnatal environmental alterations may permanently affect the lifetime vulnerability to diseases. For the interpretation of the long-term consequences it is important to understand the immediate effects. As the role of vasopressin in hypothalamic-pituitary-adrenal axis regulation as well as in affective disorders seem to be important we addressed the question whether the congenital lack of vasopressin will modify the stress reactivity of the pups and will influence the later consequences of single 24h maternal deprivation (MD) on both stress-reactivity and stress-related behavioral changes.
View Article and Find Full Text PDFGlucocorticoid hormones may have dual action on the stomach: physiological gastroprotective and pathological proulcerogenic one. In physiological conditions, even in acute stress situations, glucocorticoids have an adaptive effect on the stomach and, therefore, are gastroprotective. The findings that we review in this article suggest that glucocorticoids released during acute stress are naturally occurring protective factors that play an important role in maintenance of the gastric mucosal integrity.
View Article and Find Full Text PDFAdaptation to stress is indispensable to life and the hypothalamo-pituitary-adrenocortical axis is one of the major components of the adaptation. The hypothalamic component consists of corticotropin-releasing hormone and arginine vasopressin, with a questionable contribution of the latter. Vasopressin was more important in the regulation of the adrenocorticotropin secretion in the perinatal vasopressin-deficient Brattleboro rats than in adulthood, where its role depended on the nature of the stressor encountered.
View Article and Find Full Text PDFThe recreational party drug "ecstasy" (3,4-methylenedioxymethamphetamine MDMA) is particularly popular among young adults who are in the childbearing age and thus there is a substantial risk of prenatal MDMA exposure. We applied an intermittent treatment protocol with an early first injection on pregnant Wistar rats (15 mg/kg MDMA s.c.
View Article and Find Full Text PDFObjective: Adaptation to stress is a fundamental component of life and the hypothalamo-pituitary-adrenocortical axis (HPA) plays a crucial role in it. The place of cannabinoid influence seems to be in the brain, especially where corticotropin releasing hormone and vasopressin (AVP) secreting neurons are located. The role of AVP is considered to be more important in young than in adult rats.
View Article and Find Full Text PDFAdult male rats of the Brattleboro strain were used to investigate the impact of the congenital absence of vasopressin on plasma adrenocorticotropin, corticosterone, and oxytocin concentrations as well as the release pattern of oxytocin within the hypothalamic paraventricular nucleus (PVN), in response to a 10-min forced swimming session. Measurement of adrenocorticotropin in plasma samples collected via chronically implanted jugular venous catheters revealed virtually identical stress responses for vasopressin-lacking Brattleboro (KO) and intact control animals. In contrast, plasma corticosterone and oxytocin levels were found to be significantly elevated 105 min after onset of the stressor in KO animals only.
View Article and Find Full Text PDFAm J Physiol Regul Integr Comp Physiol
April 2009
The role of the medial basal hypothalamus (MBH) and the anterior hypothalamus/preoptic area (AH/POA) in sleep regulation was investigated using the Halász knife technique to sever MBH anterior and lateral projections in rats. If both lateral and anterior connections of the MBH were cut, rats spent less time in non-rapid eye movement sleep (NREMS) and rapid eye movement sleep (REMS). In contrast, if the lateral connections remained intact, the duration of NREMS and REMS was normal.
View Article and Find Full Text PDFThe sympathetic-adrenomedullary system and the pituitary-adrenocortical axis are linked to each other by chemical signals transferring information between both endocrine systems. Here we addressed the question of whether the neuropeptide arginine vasopressin (AVP) is involved in this type of information transfer during early postnatal development. The impact of congenital absence of AVP on the endocrine stress response was investigated using the AVP-deficient Brattleboro rat.
View Article and Find Full Text PDFStudies in arginine vasopressin (AVP)-deficient Brattleboro rats suggest that AVP is the predominant secretagogue during the perinatal period. Here we tested the hypothesis that congenital lack of vasopressin differentially modifies the stress reactivity of male and female rat pups. Vasopressin-producing (heterozygous, AVP+) and AVP-deficient (AVP-) Brattleboro rat pups of both genders were used.
View Article and Find Full Text PDFAnomalies in hormonal and neurotransmitter status during perinatal period can lead to lifespan alterations in the central nervous system. Vasopressin is present early in the brain and has various mitogenic, metabolic and physiological actions, e.g.
View Article and Find Full Text PDFIn adulthood the hypothalamo-pituitary-adrenal axis is controlled by both CRH and arginine vasopressin (AVP). However, in neonates CRH secretion is very low, whereas AVP secretion is fully functional. This suggests that the role of AVP is more pronounced in young than in adult rats.
View Article and Find Full Text PDFIn this study, we investigated the effect of chronic repeated restraint (RR) on prolactin-releasing peptide (PrRP) expression. In the brainstem, where PrRP colocalize with norepinephrine in neurons of the A1 and A2 catecholaminergic cell groups, the expression of tyrosine hydroxylase (TH) has also been examined. In the brainstem, but not in the hypothalamus, the basal PrRP expression in female rats was higher than that in the males that was abolished by ovariectomy.
View Article and Find Full Text PDFA growing body of evidence suggests that vasopressinergic activity in the hypothalamus is important in stress-related behaviors (like drug abuse) in line with a role in the regulation of the hypothalamo-pituitary-adrenal axis (HPA). We hypothesized that in the naturally vasopressin-deficient Brattleboro rat, acute and chronic morphine treatment may lead to reduced HPA axis activity. Rats were treated either with a single dose of morphine (10 mg/kg subcutaneously) and serial blood samples were taken or were treated twice daily with increasing doses of morphine (10-100 mg/kg subcutaneously) for 16 days and animals were killed by decapitation 4 or 16 h after the last injection.
View Article and Find Full Text PDFMounting evidence suggests that--beyond the well-known genomic effects--glucocorticoids affect cell function via non-genomic mechanisms. Such mechanisms operate in many major systems and organs including the cardiovascular, immune, endocrine and nervous systems, smooth and skeletal muscles, liver, and fat cells. Non-genomic effects are exerted by direct actions on membrane lipids (affecting membrane fluidity), membrane proteins (e.
View Article and Find Full Text PDFBackground And Purpose: Vasopressin plays an important role in the hypothalamo-pituitary-adrenal axis regulation as well as in stress-related disorders. A common view suggested that the role of vasopressin is especially important during chronic stresses. Here we tested the hypothesis that vasopressin-deficient rats may be more resistant to the development of chronic hypothalamo-pituitary-adrenal axis hyperactivity after chronic mild stress.
View Article and Find Full Text PDFAtrial natriuretic peptide-synthesizing neurons in the hypothalamic paraventricular nucleus constitute the major sources of ANP in the three lobes of the pituitary gland. Complete transection of the pituitary stalk eliminated 93% of ANP from the intermediate lobe, 47 and 77% from the anterior and the posterior lobes, respectively. Meantime, increased levels of immunoreactive ANP were measured in the median eminence, due to the accumulation of the peptide in the transected axons centrally to the transected stalk and in the paraventricular nucleus.
View Article and Find Full Text PDFChronic diabetes mellitus (DM) induces hyperactivity of the hypothalamo-pituitary-adrenal axis (HPA). Our present study addresses the role of vasopressin (AVP) in maintaining adrenocortical responsiveness during DM. AVP-deficient mutant Brattleboro rats were used with heterozygous controls and the V2 agonist, desmopressin was infused to replace peripheral AVP.
View Article and Find Full Text PDFDiabetes mellitus (DM), as chronic stress activates the hypothalamo-pituitary-adrenocortical axis. We examined whether arginine vasopressin (AVP) and the hypothalamic paraventricular nucleus (PVN) participate in DM-induced chronic stress symptoms. AVP-deficient Brattleboro or PVN-lesioned Wistar rats were used with heterozygous or sham-operated controls.
View Article and Find Full Text PDFThe present study was aimed at evaluating chronic stress models in mice with special attention to morphine treatment. We hypothesized that repeated periods of drug withdrawal induce chronic stress. To verify this hypothesis, mice were made dependent on morphine and then subjected to several types of repeated withdrawal.
View Article and Find Full Text PDFThe present study focuses on the topographical distribution of calcitonin gene-related peptide (CGRP)-containing cell bodies and fibers and their connections and pathways in the rat forebrain. We confirm previously reported CGRP projections from the perifornical area of the hypothalamus to the lateral septum, from the posterior thalamus to the caudate putamen and cerebral cortex, and from the parabrachial nuclei to the central extended amygdala, lateral hypothalamus, and ventromedial thalamus. Despite previous descriptions of CGRP in the central nervous system, important neuroanatomical aspects of the forebrain CGRP system remained obscure, which we addressed by using brain lesion techniques combined with modern immunohistology.
View Article and Find Full Text PDFThe hypothalamic-pituitary-adrenal (HPA) axis plays a crucial role in the stress processes. The nucleus paraventricularis hypothalami (PVN) with corticotropin-releasing hormone (CRH)-containing and arginine vasopressin (AVP)-containing neurons is the main hypothalamic component of the HPA. The glutamate, a well-known excitatory neurotransmitter, can activate the HPA inducing adrenocorticotropin hormone (ACTH) elevation.
View Article and Find Full Text PDFThe present study was aimed to test the hypothesis that behavioral sensitization to intermittent administration of morphine is accompanied by sensitization of adrenocorticotropine (ACTH) and corticosterone responses and with signs of hyperactivity of the hypothalamic-pituitary-adrenocortical function in mice. Male mice were injected subcutaneously with 40 mg/kg morphine or saline every 72 h for 16 days (in total, six injections were performed) and the effects were compared to those after single drug injection. Hormones were investigated 60 min after the last (6th) morphine or saline injection, i.
View Article and Find Full Text PDFArginine-vasopressin (AVP) has been proposed to be an important mediator during chronic stress in the regulation of the hypothalamo-pituitary-adrenal axis. In the present study we addressed the role of AVP in maintaining adrenocortical responsiveness during chronic stress using the AVP deficient mutant Brattleboro rat. Heterozygous Brattleboro rats (di/+) served as controls and were compared to homozygous rats (di/di) with diabetes insipidus.
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