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)

Cyclic AMP and cyclic GMP phosphodiesterase activities (3',5'-cyclic AMP 5'-nucleotidohydrolase, EC 3.1.4.17) were investigated in the human thyroid gland from patients with hyperthyroidism. Low substrate concentration (0.4 muM) was used. About 60% of the cyclic-AMP and 80% of the cyclic-GMP hydrolytic activities in the homogenate were obtained in the soluble fraction (105 000 X g supernatant). The thyroid gland contains two forms of cyclic-AMP phosphodiesterase, one with a Km of 1.3-10(-5) M and the second with a Km of 2-10(-6) M. Cyclic-AMP and cyclic-GMP phosphodiesterase were purified by gel filtration on a Sepharose-6B column. Cyclic-AMP phosphodiesterase activities were found in a broad area corresponding to molecular weights ranging from approx. 200 000 to 250 000 and cyclic-GMP phosphodiesterase activity was found in a single area corresponding to a molecular weight of 260 000. Cyclis-AMP phosphodiesterase activities were stimulated by the protein activator which was found in human thyroid and this stimulation was dependent on Ca2+. Stimulation of cyclic-AMP phosphodiesterase by the activator was not significant even in the presence of enough Ca2+. The effect of D,L-triiodothyronine, D,L-thyroxine, L-diiodotyrosine, L-monoiodotyrosine, L-thyronine, L-diiodothyronine, thyrotropin, hydrocortisone, adrenocorticotropin, cyclic-AMP and cyclic-GMP on the phosphodiesterase activities was studied. Cyclic-AMP, cyclic-GMP, D,L-triiosothyronine, D,L-thyroxine, adrenocorticotropin and hydrocortisone where found to inhibit the phophodiesterase. Triiodothyronine and thyroxine inhibited cyclic-AMP phosphodiesterase more effectively than cyclic-GMP phosphodiesterase. Thyroxine was a more potent inhibitor than triiodothyronine. The concentration of cyclic AMP producing a 50% inhibition of cyclic-GMP phosphodiesterase activity was 5-10(-5) M, while the concentration of cyclic GMP producing a 50% inhibition of cyclic-AMP phosphodiesterase was 3-10(-3) M. Both cyclic-AMP and cyclic-GMP phosphodiesterase activities in the homogenate of hyperthyroidism, thyroid carcinoma and adenoma were higher than in normal thyroid tissue, when assayed with a low concentration of the substrate (0.4 muM). When a higher concentration (1 mM) of cyclic nucleotides was used as the substrate, cyclic-AMP hydrolytic activity in adenoma tissue was similar to that of normal tissue, while the other activities were higher than normal.
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PMID:Human thyroid cyclic nucleotide phosphodiesterase. Its characterization and the effect of several hormones on the activity. 18 33

Thyrotropin-releasing hormone (TRH), ovine corticotropin-releasing hormone (oCRH) (both 268 nM), and mammalian gonadotropin-releasing hormone (mGnRH) (268 and 2680 nM) stimulated the secretion of bioactive thyrotropin (TSH) by Rana esculenta pituitaries (pars distalis) in vitro. Preincubation of the pituitaries with 50 ng/ml (64 nM) thyroxine (T4) for 6 hr suppressed the TRH- and oCRH-induced (268 nM) secretion of bioactive TSH, but did not affect the response of the pituitaries to 268 nM mGnRH. Triiodothyronine (T3) (64 nM) reduced both the TRH- and mGnRH-stimulated release of bioactive TSH; the response of TSH to TRH even decreased toward basal levels while a significant TSH response to mGnRH remained. In a separate experiment, pituitaries were preincubated for 6 hr with different equimolar doses of T3 and T4 (6.4, 32, and 64 nM); neither treatment affected the mGnRH-stimulated secretion of bioactive TSH. On the other hand, T4 suppressed the TSH response to TRH in a dose-dependent manner. The inhibitory effects of thyroid hormones on the TRH-induced release of bioactive TSH was present for at least 4 hr after their removal from the incubation medium. These results suggest that thyroid hormones exert a negative feedback control on the secretion of bioactive TSH in adult frogs by a direct action on the pars distalis. There may also be differences in thyroid hormone sensitivities of the TSH responses to mGnRH and TRH.
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PMID:Thyroid hormone feedback regulation of the secretion of bioactive thyrotropin in the frog. 149 May 87

The purpose of this article is to review the literature on the effects of the menstrual cycle on dependent variables in mood disorder research to inform investigators which physiological measures are likely to be significantly affected by menstrual cycle fluctuations and precisely how they might be affected. The following variables are discussed: prolactin; growth hormone; the hypothalamic-pituitary-thyroid axis (including thyrotropin, triiodothyronine, and thyroxine); the hypothalamic-pituitary-adrenal axis (cortisol, corticotropin, and beta-endorphin); melatonin; sleep; body temperature; and neurotransmitter activity (serotonergic and adrenergic systems). Body temperature and plasma and urinary norepinephrine vary predictably over the menstrual cycle. Prolactin and beta-endorphin may have peaks in the periovulatory phase, whereas serotonin levels in platelet-poor plasma may reach a nadir at that time. Triiodothyronine, thyroxine, cortisol, and melatonin do not appear to vary systematically over the course of the menstrual cycle, whereas the data for growth hormone, thyrotropin, corticotropin, and sleep are inconclusive.
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PMID:Effects of the menstrual cycle on dependent variables in mood disorder research. 759 37

Anorexia Nervosa (AN) is a psychiatric disorder characterized by the classic triad: amenorrhea, weight loss, and behavioral changes. It is generally seen in young, white women under 25 and is particularly common in adolescence. The mortality of the disease varies between 5.1% and 13%. The endocrine changes associated with AN have been studied in depth and provide strong evidence for hypothalamic dysfunction. All are secondary and reverse with weight gain. In general, gonadotropin (FSH, LH) levels are decreased in patients with AN, as well as the response to Gonadotropin releasing hormone (GnRH). Fasting growth hormone levels are elevated, but the stimulated response of Growth hormone (GH) to Growth hormone releasing hormone (GHRH) is normal and inversely correlated to body weight. Serum Growth hormone binding protein (GHBP), insulin growth factor I (IGF-I) and IGF binding protein (IGFBP) - 3 levels are all significantly decreased in patients with AN and return to normal with refeeding. IGFBP-1 and 2 are increased and return also to normal with weight gain. Serum IGF-II is decreased but not significantly. The IGFBP-3 proteolytic activity is normal. Thyroxine (T4) and Triiodothyronine (T3) while reverse T3 (rT3) is elevated. Thyrotropin stimulating hormone (TSH). TSH levels are normal with a delayed response to thyrotropin releasing hormone (TRH). Cortisol levels are normal or elevated as well as urinary free cortisol. Corticotropin (ACTH) levels are normal with decreased response to Corticotropin releasing hormone (CRH). Dexamethasone suppression test is abnormal. Sex steroids are decreased. Finally leptin levels are decreased in patients with AN while ghrelin levels are elevated. Both leptin and ghrelin levels return to control values after renutrition.
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PMID:Endocrine abnormalities in Anorexia Nervosa. 1643 12

Hot and humid weather exposes animals to high temperature and relative humidity that ultimately reduce their ability to disperse body heat. To avoid serious consequences of heat stress, it is imperative to understand animal physiological responses and biochemical changes during a state of altered body homeostasis across different seasons of the year. This study evaluated seasonal dynamics of physiological, oxidative, and metabolic responses of Nili-Ravi buffaloes to hot and humid climate. Twenty non-lactating multiparous buffaloes were enrolled for this 1-year study. Meteorological data were recorded twice daily to calculate temperature humidity index (THI). Physiological parameters including rectal temperature (RT), body surface temperature (BST), and respiratory rate (RR) were measured weekly. Blood samples were collected once in each season (spring, summer, autumn, and winter) to analyze biochemical and antioxidant parameters. We also measured activities of liver enzymes including alanine aminotransferase (ALT) and aspartate aminotransferase (AST). The results revealed a significantly higher THI value (82) during summer which resulted in a significant increase in RR and BST as compared to winter. Higher oxidative stress was observed in summer owing to significantly higher malondialdehyde (MDA) content and lower levels of serum antioxidant enzymes (GPx, SOD, and CAT) as compared to other seasons. Moreover, serum cortisol was also significantly higher while adrenocorticotropic hormone (ACTH), Triiodothyronine (T3), insulin, and growth hormone contents were significantly lower in summer. Contrarily, plasma thyroxin (T4) level was higher in summer. THI showed a positive correlation with physiological responses but a negative correlation with antioxidant parameters. Our study provides practical insights on the adaptive physiology of buffaloes and has several implications regarding the alleviation of heat stress in buffaloes to enhance the efficiency of production and reproduction under tropical climate. Our study suggests the use of appropriate cooling strategies to effectively manage the non-lactating buffaloes to avoid performance losses and animal welfare issues in summer season.
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PMID:Seasonal Dynamics of Physiological, Oxidative and Metabolic Responses in Non-lactating Nili-Ravi Buffaloes Under Hot and Humid Climate. 3310 57