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)

Rabbits were anesthetized with urethane and were given intracisternal injections of the following substances: adrenocorticotropin, beta-melanocyte stimulating hormone, choroid plexus peptide IIF, epinephrine, serotonin, histamine, oxytocin, lysine and a arginine vasopressins, acetylcholine and melatonin. The effects on the concentration of 3', 5' cyclic guanosine monophosphate (cGMP) in cerebrospinal fluid were then measured. Only melatonin and acetylcholine caused a significant (p less than 0.05) effect on cGMP concentration. Both agents increased the nucleotide's concentration within 30 min. Melatonin was about 1,000 times more potent than acetylcholine; the mininal effective doses were 1 mug and 1,000 mug, respectively.
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PMID:Injection of melatonin into cisterna magna increases concentration of 3', 5' cyclic guanosine monophosphate in cerebrospinal fluid. 18 65

A patient with Cushing's disease due to a chromophobe adenoma was studied for 243 days before pituitary surgery and evidence for periodicity in cortisol steroid production was found with cycles occurring every 85.8 days (peak-to-peak length), associated with laboratory remissions and paradoxical response to dexamethasone. The autonomy of ACTH secretion was suggested by the nonresponsiveness to repeated lysine-vasopressin stimulation tests and lack of increase in urinary 170HCS following metyrapone. A distinct response of the hyperplastic glands (as demonstrated by percutaneous adrenal venography) was obtained on several B1-24 corticotropin stimulation. The patient's hypercortisolism disappeared following removal of the chromophobe adenoma through transphenoidal hypophysectomy.
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PMID:Periodic remission in Cushing's disease with paradoxical dexamethasone response: an expression of periodic hormonogenesis. 18 34

The peptide [15, 16-D-lysine, 17, 18-D-arginine]-adrenocorticotropin-(1-19) and an all-D-retropeptide related to the amino terminal octadecapeptide of adrenocorticotropin have been synthesized by the solid-phase method. The nonadecapeptide was shown to possess 10-15% of the steroidogenic activity and 3% of the lipolytic activity of adrenocorticotropin-(1-19). The all-D-retropeptide showed no activity and exhibited no inhibitory activity in steroidogenesis and lipolysis.
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PMID:Adrenocorticotropin. 48. Synthesis and biological activity of (15, 16-D-lysine, 17, 18-D-arginine)-adrenocorticotropin-(1-19) and an all-D-retropeptide related to the amino terminal octadecapeptide of adrenocorticotropin. 18 22

The peptides alpha-MSH and MSH/ACTH 4-10 were degraded by rat brain extracts and serum to yield free amino acids among the end-products. Breakdown of these two peptides was double that of a related synthetic hexapeptide Met (0)-Glu-His-Phe-D-Lys-Phe. No significant breakdown of the hexapeptide occurred after incubation with human serum; it also had almost negligible pigmentary effects in vivo and in vitro when compared to alpha-MSH. The patterns of amino acid release indicate possible endopeptidase cleavage at Phe-Arg in alpha-MSH followed by secondary exopeptidase action to release free amino acids. For the hexapeptide, the primary cleavage point occurred at the -His3-Phe4 bond. The stability of this analog in human sera, coupled with its lower rate of degradation in the CNS, may contribute to its more potent behavioral actions in vivo.
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PMID:Biodegradation of alpha-MSH and derived peptides by rat brain extracts, and by rat and human serum. 19 Nov 54

Choroid plexus of rabbit and rat was incubated for 2-30 min at 37 degrees C under 95% O2-5% CO2 in Tyrode solution containing 10 mM glucose and 1 mM theophylline with these agents: epinephrine, norepinephrine, isoproterenol, dopamine, histamine, serotonin, arginine, and lysine vasopressins, oxytocin, angiotensin, adrenocorticotropin (ACTH), beta-melanocyte-stimulating hormone, and choroid plexus peptide IIF. After incubation, tissue and medium were analyzed for 3', 5' -cyclic adenosine monophosphate (cAMP) content. Each amine or peptide was tested initially at 1,000 microng/ml. Only ACTH and serotonin affected cAMP content of rabbit choroid plexus. At 1,000 microng/ml, these agents caused a 10 and 4 times (respectively) increase in cAMP content of tissue + medium at 2-10 min with decline in content at 10-30 min. More than 90% of the increment was located in tissue, less than 10% in medium. Minimal effective dose (MED) to cause a significant (P less than .05) accumulation of cAMP was 0.1 microng/ml (2.2 x 10(-8) M) for ACTH and 10 microng/ml (5.7 x10(-3) M) for serotonin. Only isoproterenol, epinephrine, and norepinephrine influenced cAMP content of rat choroid plexus. MED's for this effect by isoproterenol, epinephrine, and norepinephrine were .001, .01, and 10 microng/ml (4.7 x 10(-9), 5.5 x 10(-8), and 5.9 x 10(-5) M), respectively.
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PMID:Effects of hormones on 3', 5' -cyclic adenosine monophosphate in choroid plexus. 19 84

The effects of prostaglandin E1 (PGE1) and indomethacin (IDM) on the release of several pituitary hormones from the rat pituitary were investigated in vitro. An addition of 2 microng/ml of PGE1 to the medium elicited the release of growth hormone (GH) and prolactin, but not of adrenocorticotropin (ACTH) and luteinizing hormone (LH). Although the addition of 1 microng/ml of IDM alone resulted in no effect on the basal release of these hormones, IDM diminished the release of ACTH induced by crude rat hypothalamic extracts (HE) or lysine-8-vasopressin (LVP), and LH induced by HE or luteinizing hormone-releasing hormone (LH-RH). These findings implicate that a part of PGE1 action might be a direct one on the pituitary gland and PGE1 might release GH and prolactin, whereas IDM might have a direct action on the pituitary gland, and that blunt the release of these pituitary hormones induced by several stimuli.
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PMID:Effects of prostaglandin E1 and indomethacin on ACTH, prolactin, GH and LH from rat pituitary in vitro. 19 86

mRNA was isolated from cultures of AtT-20/D-16v tumor cells and translated in a mRNA-dependent reticulocyte cell-free system. The corticotropin (ACTH) product was purified by a double-antibody immunoprecipitation procedure using antisera specific for the alpha(1-24) sequence of ACTH. The product is shown by sodium dodecyl sulfate/gel electrophoresis and gel filtration on guanidine-HCl columns to be homogeneous with an apparent molecular weight (Mr) of 28,500. A product with the same molecular weight is synthesized when membrane-bound polysomes from D-16v cells are allowed to complete their nascent chains in a reticulocyte cell-free system. Mr 31,000 ACTH isolated from tumor cells has been separated into three proteins of different apparent Mr:29,000, 32,000, and 34,000. The cell-free product contains the same lysine-, methionine-, and phenylalanine-labeled tryptic peptides as the Mr 29,000 ACTH synthesized in the tumor cells. Tryptic peptide analysis also reveals the presence of the alpha(1-39) sequence in the Mr 28,500 cell-free product and suggests that there is only one copy of this sequence in the Mr 28,500 molecule.
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PMID:Characterization of a common precursor to corticotropin and beta-lipotropin: cell-free synthesis of the precursor and identification of corticotropin peptides in the molecule. 20 Sep 34

Radioactive proteins synthesized in an mRNA-dependent reticulocyte cell-free system under the direction of mRNA from AtT-20/D-16v mouse cells were isolated by specific immunoprecipitation using antiserum to either alpha(1-24) corticotropin or beta-endorphin [beta(61-91) lipotropin]. Each immunoprecipitate was fractionated by sodium dodecyl sulfate/polyacrylamide gel electrophoresis and shown to contain only one labeled protein with an apparent molecular weight of 28,500. Tryptic peptide analysis of the Mr 28,500 corticotropin and beta-lipotropin molecules isolated from the gels demonstrated that the two proteins had the same lysine, methionine, and tryptophan peptides. Four tryptic peptides from the cell-free product exhibited the same electrophoretic and chromatographic mobilities as marker tryptic peptides from bovine beta-melanotropin and porcine beta-endorphin. The identification of these peptides was confirmed by amino acid composition studies with a variety of labeled amino acids. The beta-lipotropin tryptic peptides were also shown to be located carboxy terminal to the corticotropin tryptic peptides.
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PMID:Characterization of a common precursor to corticotropin and beta-lipotropin: identification of beta-lipotropin peptides and their arrangement relative to corticotropin in the precursor synthesized in a cell-free system. 20 48

A structure-function study of alpha-melanotropin has shown that this tridecapeptide consists of two message sequences, (-Glu)-His-Phe-Arg-Trp- and -Gly-Lys-Pro-Val-NH2, and a potentiator sequence, Ac.Ser-Tyr-Ser-Met-(Glu-), when acting on its melanophore receptors. The key elements of the message, -Phe-Arg- and -Lys-Pro-, do not correspond exactly to those responsible for eliciting the effect in other tissues. It appears that alpha-MSH contains more information than would be necessary to interact with only one complementary receptor site; therefore, the topography of the hormone exposed to the binding site may be different on contact with the receptors of different target cells. To further investigate this aspect, new methods for the isolation and characterization of functional receptors must be developed. We are investigating the use of chemically well-defined, biologically active, covalent hormone-macromolecule complexes for this purpose. Another approach utilizes model receptors with a recognition pattern similar to that of the biological receptor, as described in this communication for certain highly specific antibodies.
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PMID:Mechanism of alpha-melanotropin action. 20 1

Addition of the ionophore A23187 to Y-1 mouse adrenal tumor cells in monolayer culture inhibits steroidogenesis and the steroidogenic response to corticotropin (50% inhibition at 1 . 10(-7)M). Inhibition is rapid in onset and is not overcome by addition of external Ca2+. The ionophore also inhibits stimulation of steroid synthesis by cyclic AMP. A23187 inhibits incorporation of the amino acid lysine into protein by Y-1 cells and the dose dependence of this inhibition closely resembles that of the inhibition of the steroidogenic response to corticotropin. Addition of A23187 to a subcellular system for protein synthesis prepared from Y-1 cells, inhibits incorporation of the amino acid phenylalanine into protein and this effect is not overcome by high concentrations of Ca2+. The inhibitory effect of A23187 on the response to corticotropin, like that response itself, takes place at some part of steroid synthesis after entry of cholesterol into the cells and before the side-chain cleavage of cholesterol. These studies confirm the importance of protein synthesis in the response to corticotropin and demonstrate that the effect of protein synthesized under the influence of corticotropin is exerted at some point in the events which bring substrate (cholesterol) to the mitochondrial side-chain cleavage enzyme system. It is also shown that A23187 inhibits protein synthesis, and hence the response to corticotropin, by a mechanism which is independent of the concentration of available Ca2+.
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PMID:Inhibition of steroidogenic response to corticotropin in mouse adrenal tumor cells (Y-1) by the ionophore A23187. Role of protein biosynthesis. 21 Aug 39


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