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)

Both angiotensin II and adrenocorticotropic hormone (ACTH) are well known to play a crucial role on the regulation of aldosterone production in adrenal glomerulosa cells. Recent observations suggest that the steroidogenic action of ACTH is mediated via the cAMP messenger system, whereas angiotensin II acts mainly through the phosphoinositide pathway. However, there have been no reports concerning the interaction between the cAMP messenger system activated by ACTH and the Ca2+ messenger system induced by angiotensin II. Both ACTH and angiotensin II simultaneously act on adrenal cells for regulating steroidogenesis under physiological conditions. Thus the present experiments were performed to examine the effect of ACTH on the action of angiotensin II by measuring angiotensin II receptor activity, cytosolic Ca2+ movement, and aldosterone production. The major findings of the present study are that short-term exposure to a high dose of ACTH (10(-7) M) inhibited 125I-angiotensin II binding to bovine adrenal glomerulosa cells, decreased the initial spike phase of [Ca2+]i induced by angiotensin II, and inhibition of angiotensin II-induced aldosterone production. Low dose of ACTH (10(-10) M), which did not increase cAMP formation, did not affect angiotensin II receptor activity. These studies have shown that angiotensin II receptors of bovine adrenal glomerulosa cells can be down-regulated by 1 mM dibutyryl cyclic AMP, as well as by effectors which are able to activate cAMP formation (10(-7) M ACTH and 10(-5) M forskolin). The rapid decrease in angiotensin II receptors induced by 10(-7)M ACTH was associated with a decreased steroidogenic responsiveness and a decreased rise in the [Ca2+]i response induced by angiotensin II. These studies show that the cAMP-dependent processes activated by ACTH have the capacity to interfere with signal transduction mechanisms initiated by receptors for angiotensin II.
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PMID:ACTH-induced inhibition of the action of angiotensin II in bovine zona glomerulosa cells. A modulatory effect of cyclic AMP on the angiotensin II receptor. 184 18

Lyso-platelet-activating factor (lyso-PAF): acetyl-CoA acetyltransferase (EC 2.3.1.67) enzyme activity was characterized for the first time in bovine adrenocortical tissue. It was found to be associated with the microsomal membrane fraction, in which it exhibited a specific activity of 0.4 nmol/min per mg of protein and catalytic properties similar to those described in other cell types. The adrenocortical acetyltransferase activity was increased by 2-3-fold on incubation of the preparation with purified protein kinase C (PKC) under phosphorylating condition. This activation was optimal after 5 min of incubation and paralleled an increase in PKC-catalysed 32P incorporation into microsomal proteins. Both acetyltransferase activation and protein phosphorylation were dependent on the presence of Ca2+ and phospholipids, and were blocked in the presence of the potent PKC inhibitor H-7. In the intact adrenocortical cell, angiotensin II and a potent phorbol ester (phorbol 12-myristate 13-acetate) were able to rapidly induce an increase in the biosynthesis of PAF, which was mostly released into the extracellular medium. These data suggest that bovine adrenocortical lyso-PAF acetyltransferase may be regulated by a PKC-dependent activation pathway, whereas no evidence for an additional adrenocorticotropin/cyclic AMP-dependent stimulation process was obtained in this cell type. Bovine adrenocortical cell membrane preparations were shown to possess high-affinity PAF-binding sites (Kd approximately 0.5 nM). Altogether, these observations suggest that PAF production and release may play a role in the autocrine or paracrine control of adrenocortical cell activation.
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PMID:Production of platelet-activating factor is a component of the angiotensin II-protein kinase C activation pathway in bovine adrenocortical cells. 188 37

1. Corticotropin-stimulated lipolysis in adipocytes of rats, mice, hamsters, guinea pigs and rabbits. Melanotropins elicited high lipolytic activity only in guinea pig and rabbit adipocytes. Opiate peptides were active only in rabbit adipocytes. Pituitary and chorionic gonadotropins and somatotropin were lipolytic in guinea pig adipocytes. Other hormones tested including prolactin, somatostatin, substance P, neurotensin, angiotensin II, thyrotropin releasing hormone and pancreatic polypeptide were devoid of lipolytic activity in all of the adipocytes studied. 2. In the rabbit adipocytes gamma-melanotropin was lipolytic only at high doses. At these doses the peptide inhibited the lipolytic response to a high dose of corticotropin. 3. Lipolysis stimulated by vasoactive intestinal peptide and epinephrine in rat adipocytes was antagonized by insulin. The lipolytic hormones corticotropin, epinephrine, vasoactive intestinal peptide and secretin suppressed basal and insulin-stimulated lipogenesis.
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PMID:Studies on hormonal regulation of lipolysis and lipogenesis in fat cells of various mammalian species. 196 44

A survey is given on the regulation of the formation of corticoliberin and of pro-opiomelanocortin and of ACTH, respectively, and on the significance of these compounds. The formation of pro-opiomelanocortin is furthered by corticoliberin, vasopressin, oxytocin and angiotensin II. Receptors for the binding of corticoliberin appear in numerous parts of the central nervous system. In various diseases the content of corticoliberin in the plasma and in certain tissues is changed. The inhibition of the ACTH secretion by glucocorticosteroids takes place via a decrease of the formation of corticoliberin and by a reduction of the equipment of the corticotrophic cells with receptors for its binding. The secretion of corticoliberin and of ACTH, respectively, is increased by loads, by hypoglycaemia, by blood losses, by hypoxia and by infections. In the glucocorticosteroid receptors there are 2 types with different affinity to cortisol and corticosterone.
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PMID:[Current findings in the regulation of formation of corticoliberin, pro-opiomelanocortin and ACTH as well as the efficacy of these compounds]. 196 5

The role of central angiotensin II (AII) in the shaking stress-induced adrenocorticotropic hormone (ACTH), plasma catecholamine secretion and pressor response were investigated using conscious rats. We also studied whether or not vasopressin (VP) is involved in the shaking stress-induced pressor response. The shaking stress caused significant elevations in plasma ACTH, catecholamine, and systolic blood pressure. Intra-third ventricular administration of the AII antagonist, Sar1, Ile8-angiotensin II (saralasin) significantly attenuated pressor response and plasma noradrenaline elevation but not plasma ACTH elevation. Pretreatment with the vascular-type VP receptor (V1) antagonist, d(CH2)5Tyr(Me)AVP, did not attenuate pressor response nor plasma catecholamine elevation. These results indicate that the central angiotensinergic pathway at least partly mediates the shaking stress-induced activation of the sympathetic nervous system without VP involvement, and that central AII does not mediate the ACTH secretion evoked by shaking stress.
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PMID:Role of central angiotensinergic mechanism in shaking stress-induced ACTH and catecholamine secretion. 196 26

The hypothalamus is a major source of afferents to the parabrachial nucleus (PB), but the neurotransmitters in this pathway are largely unknown. In this study, we examine the neuropeptide immunoreactivities of neurons in the hypothalamus that project to the PB by using the combined retrograde fluorescence-immunofluorescence method. After injections of the fluorescent tracer fast blue into the PB, retrogradely labeled neurons were observed in the paraventricular, dorsomedial, ventromedial, median preoptic, and anteroventral periventricular hypothalamic nuclei; in the dorsal, retrochiasmatic, and lateral hypothalamic areas; and in the medial and lateral preoptic areas. Our results show that at least five distinct neuropeptide-immunoreactive cell populations in the hypothalamus project to the PB. In the perifornical lateral hypothalamus, many neurotensin (NT)-, corticotropin-releasing factor-, dynorphin (DYN)-, angiotensin II (AII)-, and galanin-like immunoreactive (-ir) neurons were retrogradely labeled. A cluster of retrogradely labeled neurons in the juxtacapsular lateral hypothalamus stained with an antiserum against alpha-melanocyte stimulating hormone (alpha MSH). Over 50% of the retrogradely labeled cells in the arcuate nucleus were adrenocorticotropin (ACTH)-or alpha MSH-ir. Many alpha MSH- and ACTH-ir, and a few DYN-, NT- and AII-ir neurons in the retrochiasmatic area were retrogradely labeled. Only small numbers of double-labeled neurons were found in the paraventricular nucleus, and, of these, enkephalin-ir and dynorphin-ir neurons were the most common. Somatostatin-ir cells in the hypothalamus were rarely double-labeled. The chemical coding of these hypothalamic projections to the PB may provide important clues to the functional organization of these descending pathways.
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PMID:Neuropeptide organization of the hypothalamic projection to the parabrachial nucleus in the rat. 197 10

We have developed a method that separates rat adrenocortical cells by density into populations which retain zone specific properties in primary culture. Two different parenchymal populations were obtained and designated 2FASC (1.034 g/ml, 18.0 microns cell diameter) and 7GLOM (1.069 g/ml, 11.7 microns cell diameter). In freshly isolated cell suspensions the physical characteristics and differential steroidogenic responses to adrenocorticotropin and angiotensin II suggested that 2FASC cells originated predominantly from the zona fasciculata and 7GLOM cells from the zona glomerulosa. In primary culture (Dulbecco's Modified Eagle's Medium-F12 medium with 15% horse serum and 2.5% fetal bovine serum) the two populations exhibited different morphologies. 2FASC cells retained lipid and formed cohesive epithelial monolayers that remained stationary for 3 wk. 7GLOM cells were initially epithelial but rapidly lost lipid, spread, and assumed fibroblastic shapes. Both cell types were positive for the cholesterol side-chain cleavage cytochrome P-450 by immunofluorescence. Therefore, the morphologic changes seen in 7GLOM cultures were due to modulation, not fibroblastic overgrowth. This phenotypic plasticity may reflect the mesodermal origin of the adrenal cortex, and the subcapsular location of 7GLOM cells in vivo. In contrast, cells such as 2FASC which are located deeper in the cortex seem to have a more restricted, fully committed parenchymal phenotype.
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PMID:Density separation of rat adrenocortical cells: morphology, steroidogenesis, and P-450scc expression in primary culture. 216 28

To test whether angiotensinogen might be targeted to dense core secretory granules in cells containing a regulated secretory pathway, we expressed rat angiotensinogen in AtT-20 cells, a mouse pituitary cell line that has the demonstrated ability to correctly sort proteins to the constitutive or regulated pathway. We compared the pattern of secretion of angiotensinogen with that of endogenous adrenocorticotropin hormone, which is secreted by AtT-20 cells through the regulated pathway. When cells were incubated for 5 hours with dibutyryladenosine cyclic monophosphate or KCl, adrenocorticotropin hormone secretion was significantly higher than control, whereas monensin had no effect. In contrast, angiotensinogen secretion was markedly reduced by monensin, but no stimulation was observed with dibutyryladenosine cyclic monophosphate or KCl. These results make it unlikely that angiotensinogen could be cotargeted with active renin in the dense core granules of the regulated pathway. Alternative mechanisms must explain how angiotensin II is synthesized locally by tissue renin-angiotensin systems.
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PMID:Rat angiotensinogen is secreted only constitutively when transfected into AtT-20 cells. 216 1

To further study the relationship between endogenous opioid peptides and essential hypertension, we measured the concentrations of plasma leucine-enkephalin (LEK) and beta-endorphin (beta-EP) in 50 patients with essential hypertension by radioimmunoassay and investigated the effects of captopril on them. It was shown that the concentrations of plasma LEK and beta-EP in patients with essential hypertension were lower than those in normotensive subjects. No effects of age and sex were found on the concentrations of plasma LEK and beta-EP, and there was no difference in plasma LEK and beta-EP levels between patients with Stage I essential hypertension and those with Stage II essential hypertension. After a single dose of captopril, blood pressure and plasma angiotensin II decreased, plasma renin activity increased; and plasma LEK and beta-EP levels increased. Plasma LEK and beta-EP levels in patients with essential hypertension increased after one month of captopril treatment. In conclusion, the lower plasma LEK and beta-EP levels in patients with essential hypertension indicate that LEK and beta-EP may play a role in the pathogenesis of essential hypertension, and the depressor effects of captopril may act through LEK and beta-EP, besides blocking formation of angiotension II.
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PMID:[Plasma leucine enkephalin and beta-endorphin levels in patients with essential hypertension and the effects of captopril]. 216 83

The intravenous (IV) infusion of angiotensin II (AII) was administered to seven healthy male volunteers in a randomized placebo-controlled study. As expected, AII induced a significant increase in blood pressure and plasma aldosterone concentrations. AII caused a significant increase in corticotropin (ACTH) and growth hormone (GH) release, but had no effect on the release of thyrotropin (TSH) and prolactin (PRL). These findings suggest that peripherally circulating AII might influence ACTH and GH secretion in humans.
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PMID:Stimulation of growth hormone and corticotropin release by angiotensin II in man. 217 Aug 20


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