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)

A whole mount immunofluorescence method was used for the localization of immunoreactivity (IR) to four regulatory peptides and the bioamine serotonin in the nervous system of Stenostomum leucops (Turbellaria, Platyhelminthes). The flatworm S. leucops belongs to the taxon Catenulida which, according to the new phylogenetic system by Ax [2], forms a key group between the coelenterates and more advanced flatworm species. Positive IR was obtained using antisera against FMRF-amide, beta-endorphin, growth hormone releasing factor (GRF), substance P, and serotonin. The distribution patterns of these neuropeptide-like immunoreactivities differ significantly from each other. Antisera against Leu-enkephalin, bovine pancreatic polypeptide (BPP), bombesin, cholecystokinin (CCK-8), neurotensin, somatostatin, growth hormone (GH), secretin, and neurophysin II gave negative results. This primitive flatworm shows similarities with hydra in the lack of IR to anti-somatostatin, anti-Leu-enkephalin, and anti-BPP. These antisera give positive IR in more advanced flatworm species, indicating a later convergent evolution of vertebrate-like peptides within the phylum Platyhelminthes.
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PMID:Neuropeptides in a microturbellarian--whole mount immunocytochemistry. 242 Dec 67

We investigated the role of neuropeptides and adrenergic agonists in the regulation of intracellular 3',5'-cyclic adenosine monophosphate (cyclic AMP) contents in cultured Schwann cells from sciatic nerve of neonatal Sprague-Dawley rats. Of the neuropeptides examined, vasoactive intestinal polypeptide (VIP) and secretin markedly stimulated the accumulation of intracellular cyclic AMP in a time- and dose-dependent manner with half maximum at 3 and 12 min, and 2.8 X 10(-5) and 5.0 X 10(-5) M, respectively. While somatostatin, substance P, adrenocorticotropin (ACTH), beta-endorphin, and nerve growth factor (NGF) did not show any effect on cyclic AMP metabolism, isoproterenol (IP), norepinephrine (NE) and epinephrine (E) also markedly elevated the Schwann cell cyclic AMP concentration. The rank-order of potency of these adrenergic catecholamines on cyclic AMP accumulation was isoproterenol greater than norepinephrine greater than epinephrine. Simultaneous addition of VIP or secretin to the Schwann cell culture synergistically enhanced the norepinephrine-induced elevation of intracellular cyclic AMP. The effect of norepinephrine was antagonized by a selective beta 1-adrenergic antagonist but not by beta 2- nor alpha-adrenergic antagonists. These results suggest that VIP, secretin, and beta 1-adrenergic agonists alone or synergistically may play a part in the regulation of metabolism of Schwann cells mediated through a cyclic AMP-dependent mechanism.
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PMID:Peptidergic and adrenergic regulation of the intracellular 3',5'-cyclic adenosine monophosphate content in cultured rat Schwann cells. 285 16

[125I-Tyr]Somatostatin [( 125I-Tyr]SRIH) binding was found in 11 GH-secreting pituitary adenomas [Kd = 0.46 +/- 0.15 (+/- SE) nM; maximum binding, 165 +/- 35 fmol/mg protein). This binding was specific, since it was displaced by somatostatin-14 (SRIH-14), N-Tyr-SRIH-14, and SRIH-28. In contrast, a number of peptides and drugs not structurally related to SRIH, such as bombesin, dopamine, LHRH, met-enkephalin, naloxone, neurotensin, secretin, substance P, TRH, or vasoactive intestinal peptide, did not affect [125I-Tyr]SRIH binding. [125I-Tyr]SRIH specific binding also was found in PRL-secreting pituitary adenomas. The kinetic characteristics of the specific binding were similar to those of GH-secreting adenomas. However, maximal binding was one quarter that of GH-secreting adenomas (37 +/- 9 fmol/mg protein). In contrast, nonsecreting (chromophobe) tumors were devoid of any specific binding. Finally, in acromegaly, the density of [125I-Tyr]SRIH-binding sites in the adenomas was negatively correlated with plasma GH levels before surgery (r = -0.80). This suggests that somatostatinergic control is involved in GH secretion in acromegalic patients.
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PMID:Somatostatin receptors in human growth hormone and prolactin-secreting pituitary adenomas. 286 Jan 20

Specific somatostatin (SRIH) receptors on human pituitary adenoma cell membranes were characterized using [125I]Tyr11-SRIH as the radioligand. Specific binding of [125I] Tyr11-SRIH to adenoma cell membranes reached a steady state within 30 min at 25 C, and semilogarithmic analysis of the data revealed that the rate of the binding was linear at 25 C with a t1/2 of 13.2 min. Specific binding increased linearly with 5-160 micrograms plasma membrane protein. SRIH-14 and SRIH-28 inhibited [125I]Tyr11-SRIH binding to adenoma cell membranes with ID50S of 0.32 and 0.50 nM, respectively, while secretin, glucagon, gastrin, cholecystokinin-8, bombesin, TRH, LHRH, human GH-releasing factor-(1-44)-NH2, D-Ala2-met-enkephalin, gamma-aminobutyric acid and taurine did not significantly inhibit binding. All of 13 GH-secreting adenomas investigated had specific and high affinity SRIH receptors, with a dissociation constant (Kd) of 0.80 +/- 0.15 nM (mean +/- SEM) and a maximal binding capacity (Bmax) of 234.2 +/- 86.9 fmol/mg protein (mean +/- SEM). Among five of the nonsecreting pituitary adenomas examined, two had SRIH receptors with Kd values of 0.18 and 0.32 nM and Bmax values of 17.2 and 48.0 fmol/mg protein, respectively. In the remaining three, SRIH receptors were not detected. These results indicate that GH-secreting adenomas as well as some nonfunctioning adenomas have specific SRIH receptors, and hence, the function of the adenomas could be altered by SRIH.
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PMID:Specific somatostatin receptors on human pituitary adenoma cell membranes. 286 81

The jejunal contraction patterns of dogs in response to intravenous infusion of neurotensin, somatostatin, secretin, and met-enkephalin were analyzed. The peptides were given after administration of a noncaloric viscous cellulose meal. A computer was used to determine the length of spread of contraction waves, their contraction force, the contraction frequency, and the motility index. Transit rates of luminal content were assessed videofluoroscopically. During saline infusion the cellulose meal was propelled aborally at a transit rate of 3.1 +/- 1.1 cm/s; the corresponding length of spread of contraction waves was 10.3 +/- 1.5 cm. All peptides decreased both the transit rate (0.45-1.81 cm/s) and the contraction spread (3.7-6.2 cm). Neurotensin increased the contraction force, but had no effect on contraction frequency and motility index. The other peptides reduced the motility index and the frequency and force of contractions. It was shown that the peptides influenced intestinal contraction patterns and the transit rate of luminal content. The length of spread of contraction waves was found to be most important in the regulation of transit.
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PMID:Effects of neurohormonal agents on jejunal contraction spread and transit in the fed dog. 287 Sep 53

A large number of antisera mainly raised against mammalian hormones are tested immunocytochemically on the GEP-endocrine system of mouse and fish (Barbus conchonius). The endocrine pancreas of mouse and fish appeared to contain the same four endocrine cell types; insulin-, glucagon-, PP- and somatostatin-immunoreactive cells. In mouse about 13 GEP endocrine cell types are distinguished: 1. insulin-, 2. somatostatin-, 3. glucagon-, 4. PP-, 5. (entero)glucagon-/PP-like, 6. CCK-like, 7. substance P-, 8. neurotensin-, 9. VIP-, 10. gastrin-, 11. secretin-, 12. beta-endorphin-, 13. serotonin-immunoreactive cells. Based on this and a previous study at least 13 GEP endocrine cell types seems to be present in stomachless fish: 1-9 as described for mouse, 10. (entero)glucagon-like, 11. met-enkephalin, 12. VIP-like, 13. unspecific immunoreactive endocrine cells. Coexistence of glucagon and PP-like peptides is found in the gut and pancreas of mice and in the gut of B. conchonius. In mouse pancreas and fish gut, endocrine cells showing only PP- or glucagon-like immunoreactivity are found too. In mouse stomach some endocrine cells showing only PP-immunoreactivity are demonstrated. In the same region coexistence of C-t-gastrin- and FMRF-amide-immunoreactivity is found in endocrine cells. The importance of these phenomena are discussed. Enteric nerves immunoreactive with antisera raised against substance P and GRP are found in mouse, against somatostatin and met-enkephalin in both mouse and fish and against VIP in fish.
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PMID:Immunocytochemical identification and localization of peptide hormones in the gastro-entero-pancreatic (GEP) endocrine system of the mouse and a stomachless fish, Barbus conchonius. 287 13

We examined the effects of cholinergic, peptidergic and GABAergic agents on secretin secretion from canine duodenal mucosal explants incubated in organ culture media. Carbachol (10(-12) to 10(-4) M), atropine (10(-6) to 10(-4) M), hexamethonium (10(-6) to 10(-4) M), and somatostatin did not alter basal secretion of secretin. Somatostatin (10(-7) to 10(-8) M) inhibited secretin secretion stimulated by pH 4.5. Met, Leu and their D-ala2-analogs inhibited both basal and pH 4.5-stimulated secretin. Naloxone reversed the inhibition caused by met-enkephalin at pH 7.4. GABA (10(-9) to 10(-6) M) stimulated both basal and pH 4.5-stimulated secretin secretion. GABA-stimulated secretin secretion was neuronal in nature, bicuculline sensitive and was mediated via post ganglionic cholinergic neurons. GABA-stimulated secretin secretion was inhibited by both somatostatin and metenkephalin, suggesting that GABA-stimulated secretin secretion may be under the inhibitory control of peptidergic agents as well.
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PMID:Neurohormonal regulation of secretin secretion in canine duodenal mucosa in vitro. 287 46

Neuropeptides and biogenic amines known to be present in neurons or afferent terminals in the paraventricular nucleus (PVH), supraoptic nucleus (SON) and/or lateral hypothalamus (LH) were added to small areas of these structures obtained by micropuncture and cyclic adenosine monophosphate (cAMP) levels were measured. cAMP accumulation occurred in PVH, SON and LH in response to neuropeptides of the secretin family, such as vasoactive intestinal peptide (VIP) and in response to catecholamines. Bradykinin, alpha-melanocyte-stimulating (alpha-MSH), luteinizing hormone-releasing hormone (LH-RH), oxytocin and carbamylcholine stimulated cAMP accumulation selectively in one or two of the above structures. Glucagon, cholecystokinin (CCK), somatostatin (SRIF), corticotropin-releasing factor (CRF), thyrotropin-releasing hormone (TRH), adrenocorticotropin (ACTH), melanocyte-stimulating hormone (MSH), methionine enkephalin (Met-Enk), beta-endorphin, neurotensin, bombesin and angiotensin II did not effect cAMP levels while leucine enkephalin (Leu-Enk), arginine vasopressin and gamma-aminobutyric acid (GABA) elicited regionally selective decreases in basal levels of cAMP. When interactions between some of these compounds were measured, VIP and norepinephrine exerted a more than additive effect on cAMP elevation in the PVH, while the effect on cAMP of the SON and LH was additive.
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PMID:Interaction of neuropeptides and biogenic amines on cyclic adenosine monophosphate accumulation in hypothalamic nuclei. 300 57

Recent data on the immunolocalization of regulatory peptides and related propeptide sequences in endocrine cells and tumors of the gastrointestinal tract, pancreas, lung, thyroid, pituitary (ACTH and opioids), adrenals and paraganglia have been revised and discussed. Gastrin, xenopsin, cholecystokinin (CCK), somatostatin, motilin, secretin, GIP (gastric inhibitory polypeptide), neurotensin, glicentin/glucagon-37 and PYY (peptide tyrosine tyrosine) are the main products of gastrointestinal endocrine cells; glucagon, CRF (corticotropin releasing factor), somatostatin, PP (pancreatic polypeptide) and GRF (growth hormone releasing factor), in addition to insulin, are produced in pancreatic islet cells; bombesin-related peptides are the main markers of pulmonary endocrine cells; calcitonin and CGRP (calcitonin gene-related peptide) occur in thyroid and extrathyroid C cells; ACTH and endorphins in anterior and intermediate lobe pituitary cells, alpha-MSH and CLIP (corticotropin-like intermediate lobe peptide) in intermediate lobe cells; met- and leu-enkephalins and related peptides in adrenal medullary and paraganglionic cells as well as in some gut (enterochromaffin) cells; NPY (neuropeptide Y) in adrenaline-type adrenal medullary cells, etc.. Both tissue-appropriate and tissue-inappropriate regulatory peptides are produced by endocrine tumours, with inappropriate peptides mostly produced by malignant tumours.
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PMID:Endocrine cells producing regulatory peptides. 329 70

In cultured rat hepatocytes, the effects of gut hormones on bile acid uptake and release were studied. It was found that cultured hepatocytes continued to secrete bile acids into the culture medium and incorporated them effectively as a function of incubation time. Gut hormones such as secretin, glucagon, vasoactive intestinal polypeptide (VIP), peptide histidine isoleucine (PHI), gastric inhibitory polypeptide (GIP), tetragastrin, cholecystokinin-octapeptide (CCK-8), pancreatic polypeptide (PP), neurotensin substance P, beta-endorphin (beta-End), methionine-enkephalin (Met-enk), motilin, bombesin and somatostatin (SS) had no effect on bile acid uptake by cultured hepatocytes. In bile acid release studies, only secretin caused a dose-dependent stimulation of bile acid release, while other gut hormones had no effect on bile acid release into medium. These results indicate that secretin acts directly on cultured rat hepatocytes and/or bile canaliculi, besides its effect on the bile duct, and influences bile acid metabolism.
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PMID:Effects of gut hormones on bile acid uptake and release in cultured rat hepatocytes. 359 53


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