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)

An immunocytochemical analysis with 33 antisera was undertaken to investigate the localization of 25 different neurotransmitter-related antigens in the hypothalamic suprachiasmatic nucleus in the rat. To obtain estimates of relative densities of immunoreactive axons a stereological approach was used involving counting of intersections of immunoreactive axons with a superimposed semi-circle test grid. All neurotransmitter-related antigens found in perikarya within the suprachiasmatic nucleus, including those stained with antisera against bombesin, gastrin-releasing peptide, neurophysin, vasopressin, somatostatin, gamma-aminobutyrate, glutamate decarboxylase and vasoactive intestinal polypeptide were also found in axons within the nucleus. A greater number of these immunoreactive axons was found within the nucleus than in the adjacent anterior hypothalamus. The size of all immunoreactive axons in the suprachiasmatic nucleus was consistently small; immunoreactive axons were found ramifying widely in the nucleus, often ending with terminal boutons near perikarya immunoreactive for the same antigen. All neurotransmitter-related substances found in perikarya of the suprachiasmatic nucleus were also found in axons crossing over the midline to innervate the contralateral nucleus, providing an anatomical substrate for a high degree of communication between the paired nuclei. Axons immunoreactive for other putative transmitters including serotonin arising outside the nucleus were also found in high densities within the nucleus and crossing over the midline between the nuclei. Immunoreactivity for some transmitters was found in axons of similar densities within and outside the nucleus, including antisera against tyrosine hydroxylase; a small number of dopamine beta-hydroxylase and a few phenylethanolamine N-methyltransferase-immunoreactive axons were found in the SCN, suggesting that dopamine, norepinephrine and epinephrine may occur in a limited number of axons in the nucleus. Small numbers of axons immunoreactive with antisera raised against cholecystokinin, prolactin, substance P, thyrotropin-releasing hormone and choline acetyltransferase were found within the suprachiasmatic nucleus. Axons immunoreactive for luteinizing hormone-releasing hormone, adrenocorticotropic hormone, alpha-melanocyte-stimulating hormone and neurotensin were rarely found within the suprachiasmatic nucleus; axons immunoreactive for luteinizing hormone-releasing hormone, adrenocorticotropic hormone, cholecystokinin and tyrosine hydroxylase were found in both horizontal and coronal sections in the area between the left and right suprachiasmatic nuclei.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Neurotransmitters of the hypothalamic suprachiasmatic nucleus: immunocytochemical analysis of 25 neuronal antigens. 241 88

A dense peptidergic innervation has been demonstrated in the substantia innominata region in postmortem specimens of human brain using immunocytochemical techniques. A peptidergic innervation of the nucleus of Meynert - the prominent nucleus of this area containing the cholinergic cell bodies which innervate the cerebral cortex - has been demonstrated by immunostaining with antisera against the following eight neuropeptides: somatostatin, substance P, cholecystokinin octapeptide, vasoactive intestinal polypeptide, met-enkephalin, ACTH, alpha-MSH and oxytocin. Other immunocytochemical features of the substantia innominata region include a dense band of peptide immunoreactivity beneath the medial aspect of the anterior commissure and islands of somatostatin and substance P terminal immunoreactivity in the rostral part of the substantia innominata. Somatostatin immunostained cell bodies have been located in a discrete area of the bed nucleus of the stria terminalis and in the rostral portion of the substantia innominata, nucleus accumbens and the ventral part of the putamen. The dense band of peptide immunoreactivity beneath the medial aspect of the anterior commissure consists of ribbon-like processes stained with antisera against somatostatin, substance P, cholecystokinin octapeptide, vasoactive intestinal polypeptide and met-enkephalin. Less intense immunostaining of ribbon-like elements is also present in the globus pallidus. The presence of a peptidergic innervation to the nucleus of Meynert suggests a possible important modulatory role in cortical cholinergic function.
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PMID:Neuropeptide localisation in the substantia innominata and adjacent regions of the human brain. 241 23

The medial preoptic nucleus (MPN) is a sexually dimorphic complex with three major subdivisions. The cell-dense central (MPNc) and medial (MPNm) subdivisions are larger in male rats, while the cell-sparse lateral subdivision (MPNl) occupies a majority of the nucleus in females. In the present study we evaluated the distribution of possible monoaminergic and peptidergic cells and fibers within the MPN, as well as in adjacent regions of the medial preoptic area of the adult male rat. For this, we used an indirect immunohistochemical method with antisera to serotonin (5HT), dopamine beta-hydroxylase (DBH), tyrosine hydroxylase (TH), neuropeptide Y (NPY), cholecystokinin (CCK), vasoactive intestinal polypeptide (VIP), substance P (SP), neurotensin (NT), corticotropin-releasing factor (CRF), luteotropin-releasing hormone (LRH), somatostatin (SS), thyrotropin-releasing hormone (TRH), oxytocin (OXY), vasopressin (VAS), adrenocorticotropic hormone (1-24; ACTH), alpha-melanocyte-stimulating hormone (alpha-MSH), leucine-enkephalin (L-ENK), and calcitonin gene-related peptide (CGRP). The results suggest that cell bodies and/or fibers crossreacting with all of these putative neurotransmitters are differentially distributed within the MPN. Within the MPNm, the densest plexuses of fibers were stained with antisera to SP and NPY, while moderate densities of fibers were stained with anti-DBH, SS, CCK, CGRP, ACTH, and alpha-MSH, and only a few fibers were stained with anti-5HT, TH, NT, VAS, and L-ENK. Moderate numbers of SP- and L-ENK-immunoreactive cell bodies, and a few SS-, NT-, CRF-, and TRH-stained cell bodies were also found within the MPNm. The MPNc contained a dense plexus of CCK-immunoreactive fibers, as well as a few CRF-immunoreactive fibers. Both fiber types were localized almost exclusively to this subdivision, while most of the others studied here appeared to avoid it selectively. This suggests that there are relatively few inputs to the MPNc, and that they tend to avoid other parts of the nucleus, although moderate densities of DBH- and NPY-immunoreactive fibers were found in both the MPNm and MPNc. The MPNc contained several CCK-immunoreactive cell bodies as well as a moderate number of TRH-stained cell bodies. Both cell types were nearly completely localized to the MPNc. The major inputs to the MPNl studied here appear to be stained with antisera to 5HT and L-ENK, although moderate numbers of NT- and CRF- immunoreactive fibers were also found in this part of the nucleus.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Neurotransmitter specificity of cells and fibers in the medial preoptic nucleus: an immunohistochemical study in the rat. 242 28

The influence of proteinase inhibitors on the lipolytic effect of the pituitary polypeptide hormones and epinephrine in an isolated adipose tissue of rabbits and rats has been studied. Neither of proteinase inhibitors changed the basal rate of lipolysis. Trasylol, a serine proteinase inhibitor, suppressed completely growth hormone (GH) effect and partially reduced the effect of adrenocorticotropin (ACTH) and beta-lipotropin (beta-LPH) but did not change the effect of epinephrine. Bacitracin proved ineffective with regard to the effect of polypeptide hormones. Pepstatin, an acid proteinase inhibitor, partially blocked the stimulation of lipolysis by ACTH without affecting the effect of GH and beta-LPH. The influence of proteinase inhibitors on the ACTH effect in rat adipose tissue was similar to that found in rabbit tissue. The Trasylol-induced inhibition of the hormone-stimulated lipolysis decreased to a considerable extent after GH or ACTH incubation with rabbit plasma or partial GH digestion with pepsin. This decrease was not observed when plasma serine proteinases were blocked during GH incubation with plasma. The results demonstrate an involvement of some proteolytic enzymes in the realization of the polypeptide hormone lipolytic effect and permit to suppose the requirement of preliminary activation of the hormones by means of proteolytic modification.
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PMID:Involvement of proteolytic enzymes in the lipotropic effect of the pituitary polypeptide hormones. 242 65

Fifteen neuroendocrine carcinomas of the skin (Merkel cell tumors) were stained within the constraints of tissue availability by the Grimelius method and immunohistochemically for keratin, neuron-specific enolase (NSE), carcinoembryonic antigen (CEA), S-100, common leukocyte antigen (CLA), met-enkephalin, bombesin, calcitonin, ACTH, gastrin, and somatostatin. Focal argyrophilia was present in 5 of 12 tumors. All tumors tested demonstrated immunoreactivity for NSE and 5 tumors were positive for keratin. One tumors appeared to demonstrate focal ACTH-like immunoreactivity, but otherwise no immunoreactivity for the above mentioned polypeptide hormones was noted in 11 completely studied tumors. One tumor contained histologically obvious areas of squamous differentiation in addition to areas of Merkel cell tumor. In various tumors, keratin immunoreactivity was present either in areas of histologically obvious squamous differentiation, in randomly scattered single cells not histologically identifiable as squamous, or in a paranuclear dot-like distribution. Immunoreactivity for CEA, S-100 and CLA was not present in any tumors. The lack of met-enkephalin and the presence of squamous differentiation in these tumors indicates multidirectional differentiation in a fashion not phenotypically typical of Merkel cells.
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PMID:Neuroendocrine carcinoma of the skin: an immunohistochemical study of tumor markers and neuroendocrine products. 243 2

The opioid polypeptide beta-endorphin is present in fetal blood but it is not clear whether its source is the fetus or the placenta. We therefore measured beta-endorphin in extracts of fetal femoral arterial and umbilical venous blood plasma in sheep by radioimmunoassay to determine whether the fetus or the placenta is the major source of beta-endorphin in the fetal circulation. Chromatographic analysis of extracts of fetal arterial plasma showed that beta-lipotropin and other precursors of beta-endorphin made only a minor contribution to the immunoreactivity detected. Concentrations of immunoreactive beta-endorphin were higher in the femoral artery than in the umbilical vein in fetal sheep between 113 and 128 days of pregnancy. Therefore the placenta removes beta-endorphin or a closely related polypeptide of fetal origin from the umbilical circulation in sheep at this stage of gestation. Acute hypoxaemia and hypoglycaemia increase the concentrations of immunoassayable beta-endorphin in blood plasma of adult and fetal sheep, but little is known about the effects of chronic hypoxaemia or hypoglycaemia on the circulating levels of beta-endorphin and related polypeptides in the fetus. Therefore we also measured immunoreactive beta-endorphin in blood plasma from fetal sheep in which growth retardation in association with restricted placental growth was produced by removal of endometrial caruncles before mating. Intra-uterine growth retardation was accompanied by chronic hypoglycaemia and chronic hypoxaemia in the fetuses. This was not associated with higher concentrations of beta-endorphin-like immunoreactivity in fetal arterial or umbilical venous plasma, but was accompanied by significantly increased placental extraction of fetal immunoreactive beta-endorphin from the umbilical circulation.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Restriction of placental growth in sheep enhances placental metabolism of fetal beta-endorphin-like immunoreactivity. 252 77

Bovine fasciculata adrenal cells contain specific high-affinity (KD approximately 2.3 +/- 0.4 x 10(-10) M) and low-capacity (1910 +/- 300 sites per cell) corticotropin (ACTH) receptors. Pretreatment of cells with ACTH, caused in a time-(maximum effect at 48 hr) and dose-(ED50 approximately 10(-11) M, Vmax = 10(-10) to 10(-9) M) dependent manner an increase in ACTH binding. This was due to a 4-fold increase in the number of binding sites without modification of the binding affinity. The same pretreatment also enhanced the cAMP response to further ACTH stimulation in a dose-dependent manner (ED50 approximately 10(-11) M) and to a lesser extent the response to forskolin. However, pretreatment with higher concentrations of ACTH (10(-8) M) reduced the binding and the cAMP response when compared to the effect of 10(-9) M. These ACTH effects, which were mimicked by 8-bromoadenosine 3',5'-cyclic monophosphate, required de novo protein synthesis. Pretreatment with 10(-13) to 10(-11) M ACTH also enhanced the steroidogenic responsiveness to further hormonal stimulation. However, at higher concentrations the hormone induced an apparent steroidogenic desensitization that was probably related to a depletion of endogenous cholesterol, since cortisol production in the presence of 22-(R)-hydroxycholesterol was increased. Neither angiotensin-II nor atrial natriuretic factor alone modified ACTH receptors, but angiotensin-II partially blocked the stimulatory effect of ACTH. Thus, ACTH is one of the few polypeptide hormones having a positive trophic effect on its own receptors and target-cell responsiveness.
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PMID:Corticotropin positively regulates its own receptors and cAMP response in cultured bovine adrenal cells. 254 85

The behavior of steroidogenesis activator polypeptide (SAP), a recently described modulator of cholesterol side-chain cleavage activity (Pedersen, R. C., and Brownie, A. C. (1987) Science 236, 188-190), was investigated in rat adrenocortical cells using a specific radioimmunoassay. In response to a maximal dose of adrenocorticotropic hormone (ACTH) (1 nM) or of 8-Br-cAMP (1 mM), an increase in intracellular SAP begins rapidly (less than 1 min) and reaches half-maximal and maximal levels (16-fold greater than basal) at 3 and 15 min, respectively. A plateau at this maximal concentration of SAP is then maintained. The levels of intracellular SAP content and of corticosterone output exhibit a similar dose-dependent response to ACTH (EC50 = 25 and 30 pM, respectively). Treatment of ACTH-stimulated cells with cycloheximide reverses the rise in SAP (t1/2 congruent to 5-7 min). In vivo the SAP content of adrenals from quiescent rats is concordant with the circadian rhythm of the pituitary-adrenal axis; at the apex (1800 h), adrenal SAP is 13-fold higher than at the nadir (0800 h), paralleling 2- and 7-fold variations in cholesterol side-chain cleavage activity and serum corticosterone levels, respectively. At both time points, SAP levels rise in response to stress. Of the rat tissues examined, only the major steroid-forming organs (adrenal cortex and gonads) had significant levels of immunoreactive, cAMP-responsive SAP, while cAMP-unresponsive immunoreactivity was also detectable in the thymus, spleen, and brain. Considered together with the biological activity previously demonstrated for SAP in vitro, these data are consistent with its role as a cAMP-dependent, cycloheximide-sensitive modulator of steroid biosynthesis.
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PMID:The kinetics of steroidogenesis activator polypeptide in the rat adrenal cortex. Effects of adrenocorticotropin, cyclic adenosine 3':5'-monophosphate, cycloheximide, and circadian rhythm. 254 56

Corticotropin (ACTH) has two main actions in mammalian adrenal cortex: acute stimulation of glucocorticoids secretion and trophic effect which allow the expression of genes encoding for the steroidogenic enzymes. The ACTH membrane bound receptor was one of the first to be demonstrated by direct binding of labeled hormone to subcellular preparations of the adrenal cortex. However, detection and characterization of physiological relevance to ACTH receptors has been difficult, because of the low biological activity of the labeled ACTH. Introduction of a bulky iodine atom into Tyr2 and the oxidation of Met4 appear to contribute most to the loss of activity. These difficulties were overcome recently by using an [125I]-ACTH labeled only in Tyr23, which retains full biological activity. Using this labeled hormone, physiologically relevant ACTH receptors, with high affinity (KD congruent to 10-10M) and low capacity (congruent to 2000 sites/cell) have been characterized in several mammals. A second site of low affinity (KD congruent to 10(-7M) and high capacity, has been found in some studies but the significance of this second site is unknown since it cannot be related to any physiological response of adrenal cells to ACTH. In contrast with the loss of receptors and desensitization of target cells caused by most polypeptide hormones, ACTH seems to regulate positively its own receptors and the cAMP response. The molecular weight of the ACTH receptor appears to be between 83 and 100 KD.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[ACTH receptors]. 255 6

Coexistence of peptides in the small intensely fluorescent cells was demonstrated by immunocytochemistry for met-enkephalin-Arg-Gly-Leu, vasoactive intestinal polypeptide, somatostatin, neuropeptide Y and dynorphin. In the extreme example, a single cell was immunoreactive to all 5 peptides examined. Four peptides coexisted in 8% and three peptides in 13% of SIF cells. In 10% of SIF cells no peptide immunoreactivity could be detected. The most prevalent peptide was met-enkephalin (in 46% of cells), then vasoactive intestinal polypeptide (45%), somatostatin (39%), neuropeptide Y (31%) and dynorphin (24%). Met-enkephalin and vasoactive intestinal polypeptide coexisted most commonly (25%).
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PMID:Coexistence of multiple peptides in small intensely fluorescent (SIF) cells of inferior mesenteric ganglion of the guinea pig. 256 64


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