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)

[he concentrations of immunoreactive (ir-) peptides derived from the opioid peptide precursors proenkephalin A (Met-enkephalin), proenkephalin B [dynorphin (DYN)-(1-17), dynorphin-(1-8), dynorphin B, alpha-neoendorphin (alpha-NEO-E), beta-NEO-E] and proopiomelanocortin [beta-endorphin (beta-END)], and of the neurosecretory hormones vasopressin and oxytocin increased between approximately 10-fold and 50-fold from birth to adulthood in the rate hypothalamus. Gel filtration and HPLC analysis of proenkephalin B-derived opioid peptides revealed that in 3-day-old rats the predominant portion of ir-dynorphin-(1-17) and a substantial part of ir-dynorphin B consisted of a high (6000) mol wt species, a common precursor peptide for DYN-(1-17) and DYN B. In adults rats, however, authentic DYN-(1-17) and DYN B were found to be the major ir-forms. The mol wt patterns of ir-DYN-(1-8), ir-alpha-NEO-E and ir-beta-NEO-E did not differ between 3-day-old and adult rats and reflected predominantly the respective authentic opioid peptides. Taking into consideration the developmental changes in the mol wt pattern of ir-DYN-(1-17), authentic DYN-(1-17) was 5 times lower in concentration than DYN-(1-8) in 3-day-old rats, whereas in adults these opioid peptides occurred in equimolar concentrations. These findings suggest that the posttranslational processing of the precursor proenkephalin B changes in the course of postnatal development. Ir-beta-END in the hypothalamus of newborn and adult rats consisted exclusively of beta-END-sized peptides which were not (unlike those in the intermediate pituitary lobe) alpha-N-acetylated. Thus, in the hypothalamus, the enzymatic processing of the opioid peptide precursor proopiomelanocortin to beta-END seems to be fully active at birth, in contrast to that of proenkephalin B.
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PMID:Evidence for a differential postnatal development of proenkephalin B (= prodynorphin)-derived opioid peptides in the rat hypothalamus. 654 67

Using a BESM-6 computer, a computer system for accumulation and comparative analysis of amino acid sequences (AS) of protein-peptide hormones and their precursors (the so-called computer bank of protein hormone AS) was developed. A Fortran-based program designed for construction of correspondence schemes of AS and their local similarity profiles was elaborated. In combination with the previous programs this system allows a rapid inclusion of the newly deciphered sequences into the corresponding homologous groups, thus complementing the correspondence scheme and specifying the evolution profiles. A comparative analysis of AS in proopiomelanocortin (POMC), proenkephalin (PENK) and prodynorphin (PDIN) revealed evolutionary-conservative and variable sites. The conservative sites of AS are active centers of the hormones. The leu-enkephalin analog, phorphin, the fourth repeating peptide of this precursor, was detected in prodynorphin, which, similar to beta-neo-endorphin, dynorphin and rimorphin may possess a biological activity. The similarity of the effector sites of the melanotropin sequence from POMC to the met-enkephalin sequence from PENK and leu-enkephalin sequence from PDIN as well as to gastrin and cholecystokinin was established. This may suggest that the hormone-receptor complexes in target organs of these hormones are also similar.
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PMID:[Computer bank of amino acid sequences of protein hormones. Comparative analysis of the sequences in pro-opio-melanocortin, proenkephalin and prodynorphin: detection of phorphin--the 4th repeating peptide in prodynorphin]. 668 73

Extracts from guinea pig pancreas were found to contain high molecular weight enkephalin-containing polypeptides as well as free [Met]enkephalin and [Leu]enkephalin and the hexa-, hepta-, and octapeptides derived from proenkephalin. Within the limits of sensitivity of our assay (10 fmol/g of tissue), beta-endorphin and beta-lipotropin were undetectable.
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PMID:Opioid polypeptides in guinea pig pancreas. 695 48

One proopiomelanocortin peptide [beta-endorphin (BE)] and two proenkephalin A peptides [methionine enkephalin (ME) and leucine enkephalin (LE); LE derives also from proenkephalin B] were searched for in a bovine pituitary extract by capillary zone electrophoresis (CZE) and liquid secondary-ion mass spectrometry (LSIMS). A bovine pituitary homogenate was subjected to acid precipitation/centrifugation and solid-phase extraction of peptides using an octadecyl-silyl disposable cartridge. The peptide-enriched fraction was subjected to CZE at pH 2.5 and at pH 5.5., and fractions were collected under preparative CZE conditions within defined time windows where synthetic BE, ME, and LE migrate. The resolving power of CZE was demonstrated by collecting biological fractions at pH 5.5 under preparative conditions and by subsequently analyzing these fractions at pH 2.5 under analytical conditions. Preparative CZE was further performed at pH 2.5 for fractions collected at pH 5.5. LSIMS analysis of this second-dimensional CZE fraction revealed the appropriate protonated molecule ion [(M + H)+, m/z 556.4] of LE.
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PMID:Preparative and analytical capillary zone electrophoresis analysis of native endorphins and enkephalins extracted from the bovine pituitary: mass spectrometric confirmation of the molecular mass of leucine enkephalin. 748 71

beta-endorphin-like immunoreactivity (BE-li), methionine enkephalin-like immunoreactivity (ME-li), and substance P-like immunoreactivity (SP-li) were measured in the posterior pituitary of rats that experienced a 5-day space flight in a Space Shuttle. ME-li and SP-li were both significantly lower compared to the control rats. However, there was no difference in BE-li between flight and control rats. These data suggest that the space flight stress diminished the methionine enkephalin (ME) and substance P (SP) concentrations in the posterior pituitary without affecting the beta-endorphin (BE) concentration. Thus, the proenkephalin A and tachykinin, but not proopiomelanocortin, neuropeptidergic systems in the posterior pituitary may respond to this type of unique stress.
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PMID:Effects of space flight stress on proopiomelanocortin, proenkephalin A, and tachykinin neuropeptidergic systems in the rat posterior pituitary. 751 53

The opioidergic innervation of the mammalian spleen and possible species differences were investigated. Light-microscopic immunohistochemistry revealed that splenic nerves of bovine and porcine spleen, but not of rat, mouse, hamster and guinea-pig spleen contained proenkephalin-derived opioidergic innervation. Immunoreactivity to both prodynorphin and pro-opiomelanocortin was absent from splenic nerves. In bovine and porcine spleen, fibers immunoreactive for met-enkephalin, met-enkephalin-Arg-Phe, met-enkephalin-Arg-Gly-Leu, leu-enkephalin and peptide F formed perivascular plexus, traveled in trabecular connective tissue, and extended into the capsule. Spatial relationships with immune cells were apparent in the white and red pulp, excluding lymphoid follicles. Colocalization of enkephalin immunoreactivity with immunoreactivities for tyrosin hydroxylase, dopamin-beta-hydroxylase, and neuropeptide Y, but not for substance P or calcitonin gene-related peptide were found. Our results provide evidence that opioid expression in splenic innervation is strongly species-dependent and exclusively proenkephalin-derived. Colocalization with marker enzymes of noradrenergic neurons indicates a mainly postganglionic sympathetic origin of proenkephalinergic splenic innervation. Opioidergic perivascular nerves probably control the splenic blood flow. A close interrelationship of opioidergic fibers with immune cells provides the anatomical basis for direct effects of neurally released opioids on splenic immune functions.
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PMID:Pro-enkephalin opioid peptides are abundant in porcine and bovine splenic nerves, but absent from nerves of rat, mouse, hamster, and guinea-pig spleen. 762 19

1. We have determined in adrenalectomized male rats the effects of clamping plasma corticosterone and aldosterone at various concentrations on corticotropin-releasing hormone (CRH), neurotensin/neuromedin N (NT/N) and proenkephalin (pENK) mRNAs in the hypothalamus and amygdala using semi-quantitative in situ hybridization. 2. Corticosterone differentially regulated the levels of CRH and NT/N but not pENK mRNA. These effects were cell specific. CRH mRNA was reduced in the hypothalamic paraventricular nucleus (PVH), but increased in the central nucleus of the amygdala and bed nuclei of the stria terminalis. NT/N mRNA was never seen in the PVH, whereas levels increased in the central nucleus of the amygdala, but were unaffected in the lateral hypothalamic area. In those regions expressing pENK mRNA, levels were unaffected in all treatment groups. 3. CRH mRNA in both the central nucleus of the amygdala and PVH, and NT/N mRNA in the central nucleus of the amygdala were most sensitive to plasma corticosterone concentrations of less than 120 ng ml-1, i.e. those seen away from the peak of the diurnal rhythm. In adrenalectomized animals CRH mRNA in both the central nucleus of the amygdala and PVH could be set at levels usually seen in intact animals by the same plasma concentration of corticosterone. 4. The levels of CRH mRNA in the PVH and the central nucleus of the amygdala were closely correlated, while CRH and NT/N mRNA levels were similarly correlated in the central nucleus of the amygdala suggesting the existence of a common regulatory mechanism. The ED50 of their responses to corticosterone and correlations with thymus weight suggested the operation of glucocorticoid (type II) receptor mechanisms. 5. In the absence of corticosterone, aldosterone increased CRH and NT/N mRNA accumulation in the central nucleus of the amygdala, and increased CRH but not NT/N mRNA accumulation in the PVH. Aldosterone also blunted the dose-response effects of corticosterone on CRH and NT/N mRNA levels in the central nucleus of the amygdala, but not in the PVH. 6. These results suggest that, in intact animals, adrenal steroids play a major role in maintaining the levels of neuropeptide mRNAs in the PVH, bed nuclei of the stria terminalis and central nucleus of the amygdala. The results underscore the importance of cell-specific mechanisms operating to regulate the expression of neuropeptide genes in different cell types in response to diverse physiological conditions.
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PMID:Region-specific regulation of neuropeptide mRNAs in rat limbic forebrain neurones by aldosterone and corticosterone. 762 87

Applying double-labelling immunofluorescence, the peptide content of solitary and clustered small intensely fluorescent (SIF) cells, identified by an antiserum to a selective membrane glycoprotein marker, synaptophysin, was correlated with the presence of catecholamines in the rat superior cervical ganglion. Most of synaptophysin-immunoreactive solitary and clustered SIF cells apparently contained dopamine (indicated by tyrosine hydroxylase-TH) but not noradrenaline (indicated by dopamine-beta-hydroxylase-DBH). Frequently, immunoreactivities for substance P or rarely, neuropeptide Y were colocalized in TH-immunolabeled cells of both types. Immunostaining for vasoactive intestinal polypeptide was found only in solitary SIF cells and was visible in TH-immunoreactive, as well as in TH-nonreactive cells. Very few solitary SIF cells were TH- and DBH-immunoreactive. Solitary and clustered SIF cells, as a rule, were encircled by leu-enkephalin-positive fibres which were also met-enkephalin-arg6-phe7-immunoreactive, indicating proenkephalin as precursor. SIF cells were additionally approached by varicose fibres which contained immunoreactivity for calcitonin gene-related peptide (CGRP) but not for enkephalins. As observed by immuno-electronmicroscopy, fibres that were immunostained for leu-enkephalin or CGRP, deeply invaginated into SIF cell somata. In addition to close membrane appositions, CGRP-immunolabeled fibres exhibited efferent synaptic contacts wih elements of SIF cell clusters. SIF cells were non-reactive to enkephalin-antisera in control ganglia and after transection of the postganglionic nerves (axotomy); but both types exhibited leu-enkephalin in preganglionically transected ganglia (decentralization) in which enkephalin-immunoreactive fibre baskets were absent. Synthesis of enkephalin in SIF cells after decentralization was confirmed by in situ hybridization demonstrating intracytoplasmic proenkephalin messenger-RNA. The findings are indicative for a differential neurochemical equipment of SIF cells in the rat superior cervical ganglion, which mainly is independent to a topographical classification. Moreover, they demonstrate the involvement of two neuropeptides in preganglionic SIF cell innervation. Finally, the observations indicate the capacity of SIF cells for proenkephalin-expression in response to preganglionic denervation.
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PMID:Neurochemistry, connectivity and plasticity of small intensely fluorescent (SIF) cells in the rat superior cervical ganglion. 768 94

Significant post-mortem changes in peptide concentration occur within the previously unstudied timeframe, i.e. within 1 h, for the proenkephalin A, proopiomelanoccortin, and tachykinin neuropeptidergic systems in the pituitary. These data differ from data obtained in other studies that concluded that peptides are stable for up to 72 h post-mortem. The post-mortem stability of the three neuropeptides, methionine enkephalin, substance P, and beta-endorphin, was studied in the rat pituitary to test the hypothesis that significant post-mortem concentration changes of those three neuropeptides occur in the immediate post-mortem time period.
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PMID:Methionine enkephalin-like immunoreactivity, substance P-like immunoreactivity and beta-endorphin-like immunoreactivity post-mortem stability in rat pituitary. 769 Jul 65

In the present study, we used subcutaneous polyethylene glycol injections to show that a physiologically relevant stimulus, hypovolemia, will selectively increase the expression of neuropeptide genes in a restricted population of parvicellular corticotropin-releasing hormone-containing neurons in the hypothalamic paraventricular nucleus. Our results show that a large reduction in extracellular fluid maintained over approximately 20 hours is associated with a significant increase in the level of corticotropin-releasing hormone mRNA in the medial parvicellular division of the paraventricular nucleus. Additionally, there are concomitant increases in cellular levels of both neurotensin/neuromedin N and proenkephalin mRNAs. Our colocalization results show that the increases in neurotensin/neuromedin N and proenkephalin mRNAs after polyethylene glycol injection occur to a significant degree in cells that also contain corticotropin-releasing hormone mRNA. Furthermore, significant numbers of cells containing proenkephalin mRNA also contain neurotensin/neuromedin N mRNA, raising the possibility that some neurons have increased levels of all three mRNAs. Finally, in the medial parvicellular division of the paraventricular nucleus, the number of identified corticotropin-releasing hormone neurons also containing vasopressin mRNA is very low in control animals and is not increased by polyethylene glycol injections, suggesting that, within this period, activation of the vasopressin gene may not be a critical event in the neuroendocrine response of corticotropin-releasing hormone neurosecretory neurons to extracellular dehydration. Considered together with the effects of adrenalectomy on peptide colocalization, our results suggest the existence of several phenotypically distinct sets of neurons within the medial parvicellular division of the paraventricular nucleus, each characterized by its ability to regulate the expression of neuropeptide genes in a stimulus-specific manner.
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PMID:Physiological regulation of peptide messenger RNA colocalization in rat hypothalamic paraventricular medial parvicellular neurons. 772 97


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