Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01189 (beta-endorphin)
 21,003 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A variety of stressors activate the hypothalamic-pituitary-adrenal axis, with secretion and compensatory enhanced synthesis of hypothalamic corticotropin-releasing hormone (CRH). Whether CRH is a major effector in the stress response of the neonatal rat and whether the peptide's gene expression is subsequently up-regulated are not fully understood. We studied the effect of cold-separation stress on plasma corticosterone (CORT) levels and CRH messenger RNA (CRH-mRNA) abundance in the paraventricular nucleus. Rats (4-16 days old) were subjected to maximal tolerated cold-separation. CORT and CRH-mRNA abundance were measured before and at several time points after stress. Cold-separation stress resulted in a significant plasma CORT increase in all age groups studied. This was abolished by the administration of an antiserum to CRH on both postnatal days 6 and 9. CRH-mRNA increased in rats aged 9 days or older, but not in 6-day-old rats, by 4 h after stress. These results suggest the presence of robust CRH-mediated adrenal responses to cold-separation stress in neonatal rats. Before postnatal day 9, however, the compensatory increase in CRH-mRNA abundance is minimal.
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PMID:Corticotropin-releasing hormone mediates the response to cold stress in the neonatal rat without compensatory enhancement of the peptide's gene expression. 798 18

Male Wistar rats' adaptation to the periodical cold exposure (3 hours daily, 6 times a week within 2 months at the air temperature of 1-2 degrees C) and to the exercise training (swimming 1 hour daily, 6 times a week within 2 months at the water temperature of 32-33 degrees C) was resulted in a limitation of motional and vegetative manifestations of the stress reaction in the "open field" test. Activation of the stress limiting systems in the organism could be one of the main causes of these adaptive effects. There was an elevation of beta-endorphin concentration and that of the ratio "prostacycline/thromboxane" in some tissues of adapted animals.
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PMID:[The limitation of the intensity of the stress reaction under open-field test conditions through the adaptation of rats to cold and physical loading]. 813 65

Chronic stress affects the reproductive function by modifying the neuroendocrine homeostasis. The aim of the present study was to clarify the neuroendocrine and the gonadal changes following chronic intermittent stress in male rats and the action of a neuroactive drug, acetyl-l-carnitine (ALC). The effect of two different stressors, cold water swimming or ether, on central beta-endorphin (beta-EP) and GnRH contents, and on plasma testosterone levels was investigated. In addition, the response to an acute stress in chronically stressed rats, treated or untreated with ALC (10 mg/day/rat p.o.), was evaluated. The stressors were applied twice a day for 10 days, and rats were killed before, during and after the last stress session. Mediobasal hypothalamus (MBH) beta-EP and GnRH contents, and plasma testosterone levels were evaluated by radioimmunoassay. The following results were obtained: (1) both chronic swimming and ether stress caused a decrease in hypothalamic beta-EP contents; (2) MBH GnRH contents increased after chronic swimming stress but not after ether stress; (3) chronic swimming stress induced a twofold decrease in plasma testosterone levels, while no changes were observed after ether stress; (4) the treatment with ALC prevented the decrease in plasma testosterone levels after chronic swimming stress, and (5) acute stress in chronically stressed animals caused an increase in MBH-beta-EP. The present data showed that chronic swimming stress reduces the reproductive capacity and impairs the capacity to respond to the acute stress and that ALC modulates the hormonal changes to physical stress and prevents the antireproductive effect of chronic cold swimming.
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PMID:Effect of different chronic intermittent stressors and acetyl-l-carnitine on hypothalamic beta-endorphin and GnRH and on plasma testosterone levels in male rats. 823 73

Early in the development of the hypothalamic-pituitary-adrenal (HPA) axis, the rat undergoes a stress hyporesponsive period of blunted responses to several stressors including cold exposure (CE) and maternal deprivation (MD). We examined the development of the axis by monitoring adrenocorticotropin hormone (ACTH) plasma levels in an animal model of depression and/or anxiety characterized by learned helpless (LH) behavior and a dysfunctional HPA axis in adult life. On postnatal day 7 there was no significant difference in basal plasma ACTH levels between congenital (cLH) and controls, but cLH animals showed a blunted response to CE (P < 0.001). By postnatal day 14 there was a dramatic increase in ACTH response to CE (P < 0.005). On postnatal day 21 baseline ACTH and response to CE were again significantly suppressed in cLH rats. Stress responsiveness to MD was present in all groups and was insignificantly different for all ages of development between groups. These findings suggest that rats with congenital learned helplessness undergo a differential response in the development of the HPA axis in that the axis was hypersensitive at postnatal day 14 and became hyporesponsive beyond day 14, and this may, in part, account for the dysfunctional stress response observed during adulthood.
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PMID:Differential development of the stress response in congenital learned helplessness. 823 62

Using in situ hybridization we have studied the effects of different types of stressors, such as ether, immobilization, cold and swimming, on the expression of several peptide messenger ribonucleic acids (mRNAs) in the hypothalamic paraventricular nucleus of adult male rats. Paraventricular nucleus sections were hybridized using synthetic oligonucleotide probes complementary to mRNA for corticotropin-releasing hormone, neurotensin, enkephalin and thyrotropin-releasing hormone. A clear upregulation of neurotensin mRNA was seen after ether and, to a lesser extent, after immobilization stress, whereas after the two other stressors neurotensin mRNA was undetectable, as in control rats. An increase in enkephalin mRNA was observed in a selective region of the dorsal part of the medioparvocellular subdivision of the paraventricular nucleus only after ether and immobilization stress. No significant changes were seen in corticotropin-releasing hormone and thyrotropin-releasing hormone mRNA levels in any of the experimental paradigms. The present results show selective changes for various peptide mRNAs in the paraventricular nucleus after various types of stress. Significant effects could be demonstrated only on neurotensin and enkephalin mRNA after ether and immobilization stress. This suggests that adaptive changes in the rate of synthesis, processing and transport of the peptide may develop over a longer period of time.
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PMID:Effect of different types of stressors on peptide messenger ribonucleic acids in the hypothalamic paraventricular nucleus. 833 18

The corticotropin-adrenocortical response to cold pressor challenge was investigated in a study of human immunodeficiency virus (HIV) infection. Data obtained from 16 HIV-1-positive and 28 HIV-1-negative subjects are presented in this report. After the insertion of a venicatheter and following 30 min of rest, the subjects immersed one of their hands in an ice-water mixture for 2 min, and serial blood samples were obtained for the determination of ACTH and cortisol levels. The results show a significant blunting in the ACTH response and marginally lower levels of cortisol, over all time points, in HIV-1-positive subjects compared to that in HIV-1-negative subjects.
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PMID:Abnormal pituitary-adrenocortical response in early HIV-1 infection. 838 Feb 11

We studied the effect of thymopentin, a synthetic thymic peptide, on spontaneous behavior and stress models in BALB/c mice in which a WEHI 164 clone 13 murine fibrosarcoma had been implanted, as well as in the intact Sprague-Dawley rat. In untreated animals with tumors, spontaneous behavior was significantly inhibited. Resistance to swimming in cold water was also decreased in untreated animals. Thymopentin (10, 100, 1,000, and 5,000 micrograms/kg body weight, IP, 20 min before the test) enhanced spontaneous behavior in tumor-implanted mice. In addition, thymopentin partially restored floating capability of tumor bearers in either freely moving or animals on which an additional weight had been applied. In the latter test, plasma corticotropin and corticosterone levels were relatedly modified according to treatment. Rats treated with thymopentin showed a decreased sensitivity to painful stimuli. The effect of thymopentin was comparable to acetylsalicylate. Finally, thymic factors appeared capable of restoring the diminished behavioral activity of animals bearing tumors, as well as of increasing resistance to stressful stimuli and pain.
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PMID:Thymic factors influence on behavior in rodents. 838 55

The effects of the psychotropic drug etoperidone on the response to laboratory stressors was investigated in a controlled study. Cardiovascular and hormonal (catecholamines, corticotropin, and cortisol) measurements were made in a group of young, healthy volunteers during a cold pressor test (CPT), a mental arithmetic test (MAT), and insulin-induced hypoglycaemia (ITT). One-week treatment with etoperidone (ETO) (150 mg/day, orally) reduced basal and stress-induced values of systolic and diastolic blood pressure (BP) on CPT, while it did not alter catecholamine output in response to the stressor. Cardiovascular response was also attenuated after ETO on MAT, in the absence of any hormone changes. Adrenocorticotropic hormone (ACTH) and cortisol secretions were markedly reduced on ITT after ETO, whereas catecholamine outflow and cardiovascular parameters were substantially unaffected. These findings on ITT suggest that the anti-serotoninergic and anti-alpha 1-adrenergic activities of ETO may be used in the pharmacological control of the potentially detrimental consequences of the stress response.
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PMID:Effects of etoperidone on sympathetic and pituitary-adrenal responses to diverse stressors in humans. 838 90

In the studies reported here we have examined the role of the medial prefrontal cortex (MpFC) in regulating hypothalamic-pituitary-adrenal (HPA) activity under basal and stressful conditions. In preliminary studies we characterized corticosteroid receptor binding in the rat MpFC. The results revealed high-affinity (Kd approximately 1 nM) binding with a moderate capacity (42.9 +/- 3 fmol/mg) for 3H-aldosterone (with a 50-fold excess of cold RU28362; mineralocorticoid receptor) and high-affinity (Kd approximately 0.5-1.0 nM) binding with higher capacity (183.2 +/- 22 fmol/mg) for 3H-RU 28362 (glucocorticoid receptor). Lesions of the MpFC (cingulate gyrus) significantly increased plasma levels of both adrenocorticotropin (ACTH) and corticosterone (CORT) in response to a 20 min restraint stress. The same lesions had no effect on hormone levels following a 2.5 min exposure to ether. Implants of crystalline CORT into the same region of the MpFC produced a significant decrease in plasma levels of both ACTH and CORT with restraint stress, but again, there was no effect with ether stress. Neither MpFC lesions nor CORT implants had any consistent effect on A.M. or P.M. levels of plasma ACTH or CORT. Manipulations of MpFC function were not associated with changes in the clearance rate for CORT or in corticosteroid receptor densities in the pituitary, hypothalamus, hippocampus, or amygdala. Taken together, these findings suggest that MpFC is a target site for the negative-feedback effects of glucocorticoids on stress-induced HPA activity, and that this effect is dependent upon the nature of the stress.
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PMID:The role of the medial prefrontal cortex (cingulate gyrus) in the regulation of hypothalamic-pituitary-adrenal responses to stress. 839 70

Effects of opioid peptide antisera treatment on the secretion of thyrotropin (TSH) and thyrotropin-releasing hormone (TRH) in rats were studied. Anti-beta-endorphin antiserum, anti-methionine-enkephalin antiserum, or antidynorphin antiserum was injected intraperitoneally and the rats were serially decapitated. TRH levels in the hypothalamus along with plasma TRH, TSH and thyroid hormone levels were measured by individual radioimmunoassay. TRH contents in the hypothalamus decreased significantly after opioid peptide antisera treatment, while its plasma levels tended to decrease, but not significantly. Plasma TSH levels increased significantly after opioid peptide antisera injection. Plasma TRH and TSH level responses to cold as well as plasma TSH level response to TRH were enhanced with treatment of antisera to these peptides. Plasma 3,3',5-triiodothyronine levels increased significantly after treatment of antisera to these peptides. From these findings it is concluded that the treatment of opioid peptide antisera stimulates TRH and TSH secretion in rats.
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PMID:Effects of immunoneutralization of endogenous opioid peptides on the hypothalamic-pituitary-thyroid axis in rats. 840 44


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