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)

Current investigations on the immunohistochemical occurrence and co-occurrence of biogenic polypeptides in the mammalian carotid body were reviewed and extended by our own recent findings. The family of chromogranins and related peptides in glomus cells appears to have a widespread interspecies distribution, whereas other peptides investigated occur in a species-specific pattern. Immunoreactivity to antisera against opioids, which derive from the proenkephalin sequence, appears to be present in glomus cells of the rabbit, cat, dog, and a shrew. Conversely, glomus cells of pig and guinea pig predominantly are immunoreactive to cleavage products of prodynorphin, which co-occur in some cells with substance P and met-enkephalin-arg-phe, respectively. In the rat and Callithrix jacchus, opioid immunoreactivity is present in nerve fibres but not in glomus cells. Immunoreactivity to other peptides, such as neurotensin, cholecystokinin, neuropeptide Y, and galanin, is found only in one or two particular species. Neurotensin immunolabelling occurs in beagle dog glomus cells, which are known to lack substance P. Cholecystokinin immunoreactivity is present in glomus cells of dog and Callithrix, and co-exists with chromogranin A, neuropeptide Y, and substance P. Substance P appears to exist in both carotid body glomus cells and nerve fibres. Substance P immunoreactivity is present in glomus cells of all species investigated, except dog. Coexistence of substance P and calcitonin gene-related peptide (CGRP) is demonstrated in nerve fibres of the guinea pig carotid body, which originate in the petrosal and jugular ganglia. Other peptides visualized immunohistochemically in mammalian carotid body nerve fibres are vasoactive intestinal peptide and neuropeptide Y. The functional significance of the various peptides present in the carotid body is discussed.
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PMID:Immunohistochemical distribution and colocalization of regulatory peptides in the carotid body. 267 3

The central nervous system effects of neuropeptides on gastric acid and duodenal bicarbonate secretions were examined. In freely moving rats, i.c.v. administration of thyrotropin-releasing hormone (TRH), human gastrin-17 (hG-17) and the somatostatin analogue, desAA 1,2,4,5,12,13 [D-Trp8]somatostatin (ODT8-SS), significantly increased gastric acid secretion, while vasoactive intestinal peptide (VIP) had no effect. In the order of potency and efficacy, the following peptides decreased acid secretion: bombesin (BOM) greater than calcitonin gene-related peptide (CGRP) greater than calcitonin (CT) greater than corticotropin-releasing factor (CRF) greater than beta-endorphin (beta-END) greater than neurotensin (NT). In anesthetized rats, none of these peptides significantly altered proximal duodenal bicarbonate secretion. In awake, freely moving rats, cerebroventricular administration of CGRP significantly decreased while ODT8-SS, TRH and CRF significantly increased duodenal bicarbonate secretion. beta-Endorphin, VIP, CT, BOM, NT and hG-17 given i.c.v. did not significantly alter the bicarbonate response. These results indicate that neuropeptides administered into the central nervous system modulate gastric acid as well as duodenal bicarbonate secretions in awake, freely moving rats in a differentiated fashion. CGRP inhibits both acid and bicarbonate secretions, a somatostatin analogue and TRH both stimulate acid and bicarbonate secretions and CRF inhibits gastric acid but stimulates duodenal bicarbonate secretions.
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PMID:Effects of neuropeptides on gastric acid and duodenal bicarbonate secretions in freely moving rats. 271 Sep 63

Cerebrospinal fluid (CSF) concentrations of neurotensin (NT) and corticotropin-releasing hormone (CRF)-like immunoreactive materials (LIM) were measured in 22 infants and children 6 days to 15 years of age. For both neuropeptides there was a marked age-related exponential decline in CSF concentrations. The most prominent decrease in CSF neuropeptide concentrations was seen during the first 24 months of postnatal life. From 1 year and on there was no or only minimal age-associated alteration in CSF neuropeptide concentrations. In this group of children (1-15 years) mean CSF concentrations of NT-LIM and CRF-LIM were 36.8 +/- 4.32 and 65.9 +/- 4.63 pg/ml, respectively. As CSF neuropeptide concentrations are apparently independent of circulating serum concentrations, they may reflect functional activity of neuropeptide-containing neurons and therefore may be of value in the assessment of the role of peptides in the human central nervous system function and behavior.
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PMID:Cerebrospinal fluid concentrations of neurotensin and corticotropin-releasing factor in pediatric patients. 278 19

The content of beta-endorphin, neuropeptide Y and neurotensin-like immunoreactivity (beta-End, NPY and NT), and the total number of opioid binding sites, were measured in the medial preoptic area (MPOA) and mediobasal hypothalamus (MBH) of ovariectomized adult rats which were oestrogen-primed. The rats had been injected neonatally with either testosterone propionate (TP) or vehicle (oil). NPY content was found to be higher in the MPOA of animals which received TP, whereas no significant difference was observed in the MBH NPY content. However, the NT concentration in the MBH of TP-treated rats was almost twice the amount detected in oil-treated rats and with this peptide no significant changes were detected in the MPOA. Finally, beta-End and the total number of opioid binding sites were reduced in both the MPOA and MBH of the rats which were exposed to TP neonatally. Since exposure to testosterone neonatally masculinises the rat hypothalamus, to the extent that female rats cannot generate oestrogen-stimulated prolactin and luteinizing hormone surges, we suggest that the neurochemical changes reported in this paper reflect some aspects of this sexual differentiation of the rat hypothalamus.
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PMID:Effect of neonatal testosterone upon opioid receptors and the content of beta-endorphin, neuropeptide Y and neurotensin in the medial preoptic and the mediobasal hypothalamic areas of the rat brain. 282 96

[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

We have previously reported that intracameral (I.C.) administration of neurotensin (NT) potently induces a time- and dose-dependent miosis in rabbits. This study was designed to determine structure-function relationships for NT-induced miosis. NT and twelve different fragments and analogs of NT, and the structurally-unrelated peptides beta-endorphin (beta-end), somatostatin (SRIF) and thyrotropin-releasing hormone (TRH) were tested in a dose equimolar to 30 micrograms of NT for their effects on pupillary diameter (PD) in rabbits. In confirmation of previous findings, NT produced significant miosis. Followed in order of duration of effect were D-Trp11-NT, D-Tyr11-NT, the N-terminal fragment NT1-12, [Gln4] - NT and NMe-NT. The N-terminal fragment NT1-8, D-Arg8-NT, and D-Phe11-NT were weakly active. In addition, the initial N-terminal fragment NT1-6 and the C-terminal fragments NT8-13 and NT9-13 did not affect PD. D-Pro10-NT, beta-end, SRIF, and TRH were totally ineffective. The results of this investigation contribute to support a role for NT on regulation of pupillary function, and suggest that the midportion of NT appears to be critical for the expression of NT-induced miosis.
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PMID:Pupillary effects of neurotensin: structure-activity relationships. 286 86

We surveyed retinas of Raja erinacea, Mustelus canis, and Squalus acanthias for neurotransmitter substances by using antisera directed against the substances themselves or against their synthesizing enzymes. Both the peroxidase-antiperoxidase (PAP) and indirect fluorescent techniques were employed to visualize the primary antisera. In all three species positive results were obtained with antisera directed against tyrosine hydroxylase (TOH), glutamic acid decarboxylase (GAD), serotonin (5-HT), and leucine enkephalin (Lenk). Antisera directed against glucagon, neurotensin, beta-endorphin, vasoactive intestinal peptide, or bombesin failed to show any specific staining. Immunoreactivity was located in amacrine, interplexiform, and horizontal cells as well as in axons of the optic fiber layer. The four antisera labelled different amacrine cell classes, distinguished on the bases of perikaryal morphology and the distribution of cell processes in the inner plexiform layer (IPL). Amacrine cells that labelled with the same marker were seen to have different morphologies in the species studied. Thus, TOH-like immunoreactivity was distributed in layers 1, 3, and 5 of the IPL in Mustelus but only in layers 1 and 3 in Raja retina. GAD-like immunoreactivity was found diffusely over all layers of the IPL in Raja, but in Mustelus it was confined primarily to layers 1, 3, and 5 of the IPL. Lenk- and 5-HT-like immunoreactivities showed similar species variations. Two neurochemical classes of interplexiform cell were identified in this study. In Mustelus GAD-like and Lenk-like immunoreactive interplexiform cells were seen whereas in Raja only GAD-positive interplexiform cells were detected. In squalus no unequivocal demonstration of any interplexiform cell was made with these antisera. The GAD antiserum also labelled a subset of the horizontal cells in the dorsal retina of Raja. TOH and 5-HT-antisera labelled axons in the optic fiber layer of all three species but reactive ganglion cell perikarya were not identified.
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PMID:Retinal neurochemistry of three elasmobranch species: an immunohistochemical approach. 286 65

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

Aminopeptidase M (EC 3.4.11.2), which can degrade low molecular weight opioid peptides, has been reported in both peripheral vasculature and in the CNS. Thus, we have studied the metabolism of opioid peptides by membrane-bound aminopeptidase M derived from cerebral microvessels of hog and rabbit. Both hog and rabbit microvessels were found to contain membrane-bound aminopeptidase M. At neutral pH, microvessels preferentially degraded low molecular weight opioid peptides by hydrolysis of the N-terminal Tyr1-Gly2 bond. Degradation was inhibited by amastatin (I50 = 0.2 microM) and bestatin (10 microM), but not by a number of other peptidase inhibitors including captopril and phosphoramidon. Rates of degradation were highest for the shorter peptides (Met5- and Leu5-enkephalin) whereas beta-endorphin was nearly completely resistant to N-terminal hydrolysis. Km values for the microvascular aminopeptidase also decreased significantly with increasing peptide length (Km = 91.3 +/- 4.9 and 28.9 +/- 3.5 microM for Met5-enkephalin and Met5-enkephalin-Arg6-Phe7, respectively). Peptides known to be present within or in close proximity to cerebral vessels (e.g., neurotensin and substance P) competitively inhibited enkephalin degradation (Ki = 20.4 +/- 2.5 and 7.9 +/- 1.6 microM, respectively). These data suggest that cerebral microvascular aminopeptidase M may play a role in vivo in modulating peptide-mediated local cerebral blood flow, and in preventing circulating enkephalins from crossing the blood-brain barrier.
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PMID:Metabolism of opioid peptides by cerebral microvascular aminopeptidase M. 287 69


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