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)

The coexistence of varying combinations of substance P (SP), somatostatin (SOM), thyrotropin-releasing hormone (TRH) and met-enkephalin-Arg-Gly-Leu (ENK) with 5-hydroxytryptamine (5-HT) as semiquantitatively revealed by immunocytochemistry in neuronal perikarya of the raphe pallidus et obscurus in the guinea-pig was analyzed. SOM coexisted most frequently with 5-HT, followed by SP, ENK and TRH. Many 5-HT neurons were immunoreactive to 2 or more peptides such as SP/SOM, SOM/ENK, SP/ENK, SOM/TRH, SP/TRH or SOM/SP/ENK. Most of these neurons were shown to project to the spinal cord by retrograde HRP labeling combined with immunocytochemistry. After hemisection of the cervical spinal cord at the C5 level, ENK and 5-HT immunoreactive nerve terminals in the ipsilateral intermediolateral nucleus of the thoracic spinal cord were decreased in number. The results indicate that neurons in the raphe pallidus et obscurus projecting to the spinal cord can be classified into subpopulations according to which peptides coexist with 5-HT, and may have different functions.
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PMID:Coexistence of varying combinations of neuropeptides with 5-hydroxytryptamine in neurons of the raphe pallidus et obscurus projecting to the spinal cord. 257 20

1. Preliminary, general chemical characteristics of substances in artificial sea water (ASW) washed through stimulated body wall (SBW) and in hemolymph taken from noxiously stimulated animals (SHL) were consistent with those of classical neurotransmitters, amino acids, and small- to medium-sized peptides. 2. 5-Hydroxytryptamine (5HT) and acetylcholine (ACh), unlike SBW and SHL, caused relaxation when perfused into isolated body wall. FMRFamide produced a biphasic response--brief contraction followed by prolonged relaxation. 3. Small cardioactive peptide (SCPB) caused body wall contractions similar to those produced by SBW and SHL, except that SCPB contractions displayed more desensitization and were completely blocked by 30 mM CoCl2. SCPB and SBW contractions were synergistic. 4. Dopamine caused persistent body wall contractions similar to those of SBW and SHL. Dopamine contractions were reduced but not blocked by 30 mM CoCl2. Unlike SBW activity, dopamine activity was reduced by alkalinization. 5. Glutamate and taurine produced strong but usually short-lasting body wall contractions. Adenosine, octopamine, arginine vasotocin, and cholecystokinin (CCK-8) caused weak or variable contractions. Met-enkephalin and somatostatin caused no obvious body wall responses. 6. When superfused over the fully sheathed abdominal ganglion, FMRFamide, met-enkephalin, glutamate, aspartate, and taurine reduced the magnitude of the gill-withdrawal reflex elicited by siphon nerve stimulation. 7. Taken together with earlier results, these data suggest a preliminary framework for trauma signal pathways. It is proposed that stress hormones (perhaps including FMRFamide, SCPs, 5HT, and dopamine) are released into hemolymph from neuroendocrine cells. Effective amounts of active intracellular solutes such as amino acids may also be released by extensive cellular rupture. Various humoral signals produce slow effects that contribute to hemostasis, balling up, increased cardiac output, and reflex suppression.
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PMID:Humoral factors released during trauma of Aplysia body wall. II. Effects of possible mediators. 276 Feb 88

Asp-Thr-Met-Arg-Cys-Met-Val-Gly-Arg-Val-Tyr-Arg-Pro-Cys-Trp-Glu-Val, melanin concentrating hormone (MCH), is a cyclic hormone possessing both MCH-like (melanin granule aggregating effect) and melanocyte stimulating hormone (MSH)-like (melanin granule dispersing effect) activities. Nine ring-contracted analogues were synthesized and characterized for their melanotropic activity on the fish (Synbranchus marmoratus) and frog (Rana pipiens) bioassays. In most cases, these analogues were totally devoid of MCH-like agonist activity, demonstrating the essential role of the disulfide bridge between residues 5 and 14 of the hormone. [Ala5, Cys10]MCH, for example, was totally devoid of MCH-like activity. This analogue, like alpha-MSH, however, antagonized the melanosome aggregating actions of MCH on fish melanocytes. The antagonistic activity of the analogue, like that of alpha-MSH, was Ca2+-dependent. Evidence suggested that this antagonism of MCH activity was related to the intrinsic MSH-like activity of the analogue. These results suggest that MCH and alpha-MSH may be structurally and, therefore, evolutionarily related.
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PMID:Melanin concentrating hormone analogues: contraction of the cyclic structure. II. Antagonist activity. 278 30

A novel neuropeptide which stimulates adenylate cyclase in rat anterior pituitary cell cultures was isolated from ovine hypothalamic tissues. Its amino acid sequence was revealed as: His-Ser-Asp-Gly-Ile-Phe-Thr-Asp-Ser-Tyr-Ser-Arg-Tyr-Arg-Lys-Gln- Met-Ala- Val-Lys-Lys-Tyr-Leu-Ala-Ala-Val-Leu-Gly-Lys-Arg-Tyr-Lys-Gln-Arg-Val-Lys-Asn-Lys - NH2. The N-terminal sequence shows 68% homology with vasoactive intestinal polypeptide (VIP) but its adenylate cyclase stimulating activity was at least 1000 times greater than that of VIP. It increased release of growth hormone (GH), prolactin (PRL), corticotropin (ACTH) and luteinizing hormone (LH) from superfused rat pituitary cells at as small a dose as 10(-10)M (GH, PRL, ACTH) or 10(-9)M (LH). Whether these hypophysiotropic effects are the primary actions of the peptide or what physiological action in the pituitary is linked with the stimulation of adenylate cyclase by this peptide remains to be determined.
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PMID:Isolation of a novel 38 residue-hypothalamic polypeptide which stimulates adenylate cyclase in pituitary cells. 280 20

The relationship between the neuropeptides leu-enkephalin, met-enkephalin, kentsin (a contraceptive tetrapeptide) and ethanol was studied in the male rat. This was pursued by assessing the effect of these peptides and some of their amino acid constituents on voluntary drinking of ethanol by rats with preference to alcohol intake. The in vitro effect of some of kentsin amino acids constituents on rat liver alcohol and aldehyde dehydrogenase was also studied. Intraperitoneal injection of leu-enkephalin, but not met-enkephalin, produced a delayed increase in voluntary ethanol drinking by the rat. Injection of identical doses of kentsin produced a much lesser effect than the leu-enkephalin treatment. The separate or combined treatment with phenylalanine and leucine, resulted in decreased voluntary consumption of ethanol. Coadministration of glycine or tyrosine alone or both combined did not influence ethanol drinking. Coadministration of tyrosine or glycine with leucine negated the leucine effect on ethanol drinking. Both L-arginine and L-proline, the two amino acids component of kentsin, decreased the specific activity of rat liver mitochondrial aldehyde dehydrogenase in vitro at 10(-3) mol concentration. The results suggest an interrelationship between the peptides studied and ethanol preference. The data also indicates that some of kentsin action on ethanol drinking may be related to the effect of some of its degradation product on hepatic ethanol-derived acetaldehyde metabolism and/or may be related to the endocrine property of kentsin.
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PMID:Enkephalins, their constituents and voluntary drinking of ethanol by the rat. 281 54

The minimal sequence required for biological activity of alpha-MSH (alpha-melanotropin, alpha-melanocyte stimulating hormone) was determined in the frog (Rana pipiens) skin bioassay. The sequence required to elicit measurable biological activity was the central tetrapeptide sequence, Ac-His-Phe-Arg-Trp-NH2 (Ac-alpha-MSH6-9-NH2), which was about 6 orders of magnitude less potent than the native tridecapeptide. Smaller fragments of this sequence (Ac-His-Phe-NH2, Ac-Phe-Arg-NH2, Ac-His-Phe-Arg-NH2) were devoid of melanotropic activity at concentrations as high as 10(-4) M. We were unable to demonstrate biological activity for the tetrapeptide, Ac-Phe-Arg-Trp-Gly-NH2 (Ac-alpha-MSH7-10-NH2), and for several carboxy terminal analogues including Ac-Lys-Pro-Val-NH2 (Ac-alpha-MSH11-13-NH2). We prepared a series of fragment analogues of alpha-MSH in an attempt to determine the contribution of each individual amino acid to the biological activity of the native hormone. The minimal potency of Ac-alpha-MSH6-9-NH2 could be enhanced about a factor of 16 by the addition of glycine to the C-terminus, yielding Ac-alpha-MSH6-10-NH2 (Ac-His-Phe-Arg-Trp-Gly-NH2). Addition of glutamic acid to the N-terminus provided the peptide, Ac-alpha-MSH5-10-NH2, which was only slightly more potent than Ac-alpha-MSH6-10-NH2, indicating that position 5 contributes little to the biological potency of alpha-MSH in this assay. Addition of methionine to the N-terminus of Ac-alpha-MSH5-10-NH2 resulted in the heptapeptide, Ac-alpha-MSH4-10-NH2, which was only about 4-fold more potent than Ac-alpha-MSH5-10-NH2. Addition of lysine and proline to the C-terminal of the Ac-alpha-MSH4-10-NH2 sequence yielded the peptide, Ac-alpha-MSH4-12-NH2 with a 360-fold increase in potency relative to Ac-alpha-MSH4-10-NH2. This peptide was only about 6-fold less potent than alpha-MSH. A series of Nle-4-substituted analogues also were prepared. Ac-[Nle4]-alpha-MSH4-10-NH2 was about 4 times more potent than Ac-alpha-MSH4-10-NH2. Ac-[Nle4]-alpha-MSH4-11-NH2 also was about 4 times more potent than Ac-alpha-MSH4-10-NH2, demonstrating that lysine-11 contributes somewhat to the biological activity of alpha-MSH on the frog skin melanocyte receptor.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:alpha-Melanotropin: the minimal active sequence in the frog skin bioassay. 282 31

A 34-amino acid peptide and three other structurally related peptides were isolated from rabbit fetal and adult lung. These cationic arginine- and cysteine-rich peptides inhibit corticotropin (ACTH)-stimulated rat adrenal cell corticosterone production. The peptide was called corticostatin (CSI). CSI was purified by reverse-phase HPLC and was shown to be homogenous from its amino acid analysis. Its sequence was determined on a gas-phase sequenator. The structure of CSI is Gly-Ile-Cys-Ala-Cys-Arg-Arg-Arg-Phe-Cys-Pro-Asn-Ser-Glu-Arg-Phe-Ser-Gly- Tyr-Cys - Arg-Val-Asn-Gly-Ala-Arg-Tyr-Val-Arg-Cys-Cys-Ser-Arg-Arg. CSI was found to markedly inhibit ACTH-stimulated corticosterone production by rat adrenal cells in vitro but did not affect basal levels. CSI did not affect the stimulation of aldosterone synthesis by angiotensin II in rat zona glomerulosa cells but it did suppress ACTH-stimulated aldosterone synthesis in whole adrenal cells, demonstrating that CSI is a specific inhibitor of ACTH-stimulated corticosteroid synthesis. The minimum effective concentration of CSI inhibiting ACTH-stimulated (33 pM) corticosterone production was 5 nM (20 ng/ml), the ED50 (50% effective dose) was 25 nM and steroidogenesis was completely inhibited at concentrations greater than 500 nM (2 micrograms/ml).
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PMID:Isolation and structure of corticostatin peptides from rabbit fetal and adult lung. 282 94

Peptide hormones are synthesized from larger precursors by cleavages at paired basic residues. We have isolated a pro-hormone converting enzyme from bovine neural and intermediate lobe secretory vesicles that cleaves pro-vasopressin and pro-opiomelanocortin at Lys-Arg residues to yield vasopressin, and adrenocorticotropin/endorphin-related peptides, respectively. The enzyme from both lobes is an aspartyl protease of approximately 70,000 Da, is a glycoprotein and has an optimum pH range of 4.0-5.0. Present within the same secretory vesicles is an aminopeptidase B-like enzyme which is a metalloprotease that is inhibited by Co2+ and Zn2+. This enzyme may play a role in trimming off the N-terminal extended basic residues from peptides liberated by the pro-hormone converting enzyme.
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PMID:Pro-opiomelanocortin and pro-vasopressin converting enzyme in pituitary secretory vesicles. 284 Sep 73

N alpha-Acetyltransferase, which catalyzes the transfer of an acetyl group from acetyl coenzyme A to the alpha-NH2 group of proteins and peptides, was isolated from Saccharomyces cerevisiae and demonstrated by protein sequence analysis to be NH2-terminally blocked. The enzyme was purified 4,600-fold to apparent homogeneity by successive purification steps using DEAE-Sepharose, hydroxylapatite, DE52 cellulose, and Affi-Gel blue. The Mr of the native enzyme was estimated to be 180,000 +/- 10,000 by gel filtration chromatography, and the Mr of each subunit was estimated to be 95,000 +/- 2,000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The enzyme has a pH optimum near 9.0, and its pI is 4.3 as determined by chromatofocusing on Mono-P. The enzyme catalyzed the transfer of an acetyl group to various synthetic peptides, including human adrenocorticotropic hormone (ACTH) (1-24) and its [Phe2] analogue, yeast alcohol dehydrogenase I (1-24), yeast alcohol dehydrogenase II (1-24), and human superoxide dismutase (1-24). These peptides contain either Ser or Ala as NH2-terminal residues which together with Met are the most commonly acetylated NH2-terminal residues (Persson, B., Flinta, C., von Heijne, G., and Jornvall, H. (1985) Eur. J. Biochem. 152, 523-527). Yeast enolase, containing a free NH2-terminal Ala residue, is known not to be N alpha-acetylated in vivo (Chin, C. C. Q., Brewer, J. M., and Wold, F. (1981) J. Biol. Chem. 256, 1377-1384), and enolase (1-24), a synthetic peptide mimicking the protein's NH2 terminus, was not acetylated in vitro by yeast acetyltransferase. The enzyme did not catalyze the N alpha-acetylation of other synthetic peptides including ACTH(11-24), ACTH(7-38), ACTH(18-39), human beta-endorphin, yeast superoxide dismutase (1-24). Each of these peptides has an NH2-terminal residue which is rarely acetylated in proteins (Lys, Phe, Arg, Tyr, Val, respectively). Among a series of divalent cations, Cu2+ and Zn2+ were demonstrated to be the most potent inhibitors. The enzyme was inactivated by chemical modification with diethyl pyrocarbonate and N-bromosuccinimide.
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PMID:Purification and characterization of an N alpha-acetyltransferase from Saccharomyces cerevisiae. 284 92

The molluscan neuropeptide, Phe-Met-Arg-Phe-NH2 (FMRFamide), the mammalian opioid peptide met-enkephalin, and their common analogues, met-enkephalin-Arg6-Phe7 (YGGFMRF) and Tyr-Gly-Gly-Phe-Met-Arg-Phe-amide (YGGFMRFamide), were injected into the lateral ventricle of the rat; the cardiovascular effects were studied. FMRFamide caused a rapid, transient elevation in blood pressure accompanied by a great increase in pulse pressure. These effects were followed by secondary increases in blood and pulse pressures. Met-enkephalin produced an initial reduction in blood pressure which was followed by a gradual increase at the higher of two test doses (300 nmole). Injection of YGGFMRF resulted in a gradual increase in blood pressure. This response resembled that to met-enkephalin. The initial response to YGGFMRFamide was similar to that to FMRFamide: increases in both blood and pulse pressures after injection. However, the secondary effect of YGGFMRFamide, a prolonged reduction in blood pressure, was not produced by FMRFamide. These results suggest that the initial excitatory cardiovascular responses may be due to the presence of the C-terminal amide. All of the cardiovascular effects of injecting these peptides into the lateral ventricle were abolished by pre-treatment with naloxone in a dose that, itself, produced no cardiovascular changes. In conclusion, these peptides seem to act via the naloxone sensitive opiate receptors in the rat brain.
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PMID:Cardiovascular effects of intraventricular injection of FMRFamide, Met-enkephalin and their common analogues in the rat. 286 Oct 46


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