Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P20366 (substance P)
 21,176 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effects of chronic treatment with the ACTH-(4-9) analogue Org 2766, alpha-MSH, and gamma 2-MSH were studied on T-maze reversal learning and on behavior assessed on the basis of open-field and other gross behavioral activities, grasping responses, inspection of various reflexes and electrical footshock sensitivity of rats with parafascicular lesions or sham-lesions. Repeated administration of Org 2766 and alpha-MSH to parafascicular area-lesioned rats resulted in functional recovery of impaired T-maze reversal learning. The structurally related neuropeptide gamma 2-MSH was without any effect. The alpha-MSH effect did not depend on time after lesioning as treatments during the first or second post-operative week were equally effective. Chronic peptide treatments did not change disturbed motor functions of parafascicular-lesioned rats, as measured by open-field activity, other gross behavioral activities and grasping responses. Since acute peptide treatments did not affect the impaired reversal learning performance of lesioned rats, the beneficial effect of Org 2766 and alpha-MSH could not be explained as a short-term effect on attention and motivation. It was more likely to be an accelerated recovery of cognitive function as a result of long-term neurotropic influences.
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PMID:Beneficial effect of chronic treatment with Org 2766 and alpha-MSH on impaired reversal learning of rats with bilateral lesions of the parafascicular area. 299 19

A 54 year old woman suffered from acromegaly due to a pancreatic islet cell tumour producing GHRH. The tumour was demonstrated on CT scan. The diagnosis was established from elevated plasma levels of GHRH, GH and prolactin, and by the lack of signs of a pituitary adenoma in trans-sphenoidal surgery. Acromegaly was cured by tumour removal. Light microscopically, the tumour showed a medullary and microlobular pattern. The cells were large and often cuspidal. Small granules were found in semi-thin sections. Small aggregations of amyloid fibres were seen, mostly around capillaries. Immunocytochemistry revealed GHRH, NSE, neurotensin, serotonin, VIP and PP. S 100 was positive only in nerve fibres. Staining for GH, ACTH, calcitonin, alpha-HCG, beta-HCG, insulin, glucagon, gastrin, substance P, bombesin and somatostatin was negative. Ultrastructure showed oval partly lobulated nuclei with small nucleoli, moderate amounts of rough endoplasmic reticulum, many free ribosomes, some large Golgi fields and small numbers of secretory granules measuring 150 nm or, in a few cells, 650 nm. Only 4 other cases of pancreatic endocrine tumours causing acromegaly by ectopic GHRH secretion are described in the literature and these were similar to our case in many respects.
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PMID:Morphology of a GHRH producing pancreatic islet cell tumour causing acromegaly. 301 79

During the course of evolution, species have increased in complexity, and their nervous systems have evolved correspondingly with an increase in the diversity of their capabilities to respond. Part of that diversity has resulted from an increase in cell types and numbers and their interconnections. In addition, much of it comes from the panoply of neurotransmitters available, of which the neuropeptides represent a major portion. The application of the techniques of molecular biology to the nervous system has led to an appreciation of some of the genetic means by which such diversity can be generated. The cloning and sequencing of peptide precursor genes has shown the existence of gene families, genes with duplications of internal sequences, and genes evolutionarily related to one another, suggesting that one response to the increasing complexity of the organism has been a genetic diversification of the precursor population for peptides. As the precursor genes evolved and thereby provided increasing numbers of peptides, the receptor genes may have evolved simultaneously to provide diversification in the responses to these peptides (for example, the opioid peptide precursors) (Comb et al 1983). The precursor sequences obtained have led not only to the predictions of new peptides but also to the discovery of alternative methods of generating diversity from a single gene. At one extreme, the gene is translated into a polyprotein containing several peptides, which are produced in and released from the same cell. At the other extreme, the nuclear transcript of the gene is differentially spliced such that one peptide is expressed in one tissue and another in a different tissue (Calcitonin-CGRP), or one peptide may be expressed with or without a second peptide in different cells (substance P-substance K). The net result is either one neuron producing a multiplicity of responses to several co-released peptides derived from a polyprotein (POMC or PE) or a tissue- or cell-specificity in terms of which peptide is produced and released. Numerous applications have been made utilizing the cDNA probes generated from the cloning of neuropeptide precursors. Hybridization analyses, including in vitro transcription run-off, have demonstrated that the transcription of neuropeptide genes is regulated by transsynaptic activation of transmitter receptors located in the neuronal membrane, or by hormones, or by as yet unveiled mechanisms. Hybridization techniques have allowed assessment of the dynamic state of neuropeptides functioning as neuromodulators.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Hybridization approaches to the study of neuropeptides. 351 86

Data are presented, demonstrating the action of a number of oligopeptides on biological motivations of hunger, fear, self-stimulation and on alcohol addiction. In the structure of animals feeding motivation, such oligopeptides take part as beta-lipotropin and its fragments, ACTH, pentagastrin, delta-sleep inducing peptide (DSIP), substance P; in organization of defensive motivation--angiotensin II (AII), DSIP, substance P, bradykinin, beta-endorphin etc.; in organization of self-stimulation--AII, DSIP, bradykinin, ACTH, beta-endorphin etc. It is established that most of the above oligopeptides, injected to the brain lateral ventriculi, inhibit biological motivations, and only some of them have an activating action. On the basis of experiments, a hypothesis is formulated that oligopeptides act as a feedback between the genome of brain neurones and pacemaker cells of motivation centres of the hypothalamus area. Some oligopeptides elaborated by neuronal genomes under the action of dominating motivation, activate--and the other--suppress the activity of motivation hypothalamus centres.
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PMID:[Oligopeptides in the development of biological motivations]. 357 22

Five carcinoid tumors of the thymus were screened immunohistochemically for the occurrence of neuropeptides (ACTH, calcitonin, calcitonin gene-related peptide, cholecystokinin, gastrin, neurotensin, somatostatin, substance P), as well as of serotonin, chromogranin A, and neuron-specific enolase. Most of the patients exhibited local symptoms evoked by growing tumor masses in the upper mediastinum without any clinical evidence of endocrine activity. Light and electron microscopic examination showed characteristic uniform large epithelial cells in polar or palisade arrangement, containing variable amounts of electron-dense secretory granules. Only a few of the tested neuropeptide antisera reacted with the investigated tumors. Cholecystokinin-immunoreactive cell populations were seen in all tumors. Expression of neurotensin could be observed in three neoplasms, two of which also exhibited ACTH immunoreactivity. Chromogranin A-immunoreactive cells were found in two neoplasms. Neuron-specific enolase showed strong staining in three tumors, one of the tumors also being immunoreactive for calcitonin. The results were confirmed by control reactions. Apart from the demonstration that conventional marker proteins are not reliable in identifying all carcinoid tumors, the present study proves that the visualization of neuropeptide-immunoreactive cells in thymus carcinoids does not necessarily correspond to the manifestation of the clinical symptoms. Furthermore, each of the investigated neoplasms, as also known from other carcinoid tumors, appears to be able to produce more than one hormone.
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PMID:Carcinoid tumors of the thymus. An immunohistochemical study. 366 30

The intracerebroventricular (i.c.v.) injection of oxytocin, in doses ranging from 5 to 90 ng (5-90 pmol) induced penile erection and yawning in male rats. Such response was not induced by doses of the peptide higher than 100 ng, nor by equimolar doses of i.c.v. [Arg8]vasopressin, ACTH-(1-24), alpha-MSH, rat corticotropin-releasing factor (rCRF), delta sleep-inducing peptide, neurotensin or substance P. Oxytocin-induced penile erection and yawning were prevented by atropine and morphine, but not by methylatropine or the opiate antagonist naloxone. Haloperidol, a dopamine receptor antagonist, was ineffective at low doses; it partially prevented penile erection but not yawning at high doses. Since oxytocin is present not only in the neurohypophysis but also in other brain areas, our results suggest that oxytocin is implicated in the regulation of penile erection and yawning, and provide further evidence that oxytocin acts as a neuropeptide in the central nervous system.
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PMID:Oxytocin: an extremely potent inducer of penile erection and yawning in male rats. 379 49

Twenty-seven cases of medullary carcinoma of the thyroid gland (MCT) were studied by light microscopy, immunocytochemistry, and electron microscopy. Immunoreactivity for neuron-specific enolase (NSE) and calcitonin was present in all tumors. The numbers of peptides and serotonin demonstrated in each case varied from one to eight. Bombesin was present in 18 of the 27 cases, serotonin in 15, leu-enkephalin in 8, somatostatin in 8, gastrin in 3, substance P in 1, vasoactive intestinal peptide (VIP) in 1, and ACTH in 1. Insulin and glucagon were not encountered in any of the tumors. Immunoreactivity for thyroglobulin was seen in five primary tumors as well as in one lymph node metastasis. The finding of concurrent production of calcitonin and thyroglobulin within the same tumor is enough to question the dogma of the separate origin of follicular cells and C-cells. We were unable to attach any clinical importance to the production of multiple peptides and/or amines.
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PMID:Medullary carcinoma of the thyroid gland: an immunocytochemical study. 390 54

gamma-Endorphin generating endopeptidase (gamma EGE) activity is an enzyme activity which converts beta-endorphin into gamma-endorphin and beta-endorphin-(18-31). The inhibitory potency on gamma EGE activity of neuropeptides and analogues or fragments of neuropeptides was tested. Dynorphin-(1-13) (IC50: 0.14 microM), human beta-endorphin-(1-31) (IC50: 15.5 microM), porcine ACTH-(1-39) (IC50: 6.3 microM), and substance P (IC50: 26 microM) had an inhibitory activity on gamma EGE activity. beta-Endorphin-(18-31) (IC50: 0.35 microM) but not gamma-endorphin potently inhibited gamma EGE activity. The IC50 of poly (Lys)40-60 was 0.8 microM. It is concluded that 1) gamma EGE activity is strongly inhibited by its product beta-endorphin-(18-31), 2) the enzyme is strongly inhibited by peptides with an aromatic amino acid at the NH2-terminal and/or basic amino acids in the COOH-terminal of the peptide chain.
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PMID:Inhibition of gamma-endorphin generating endopeptidase activity of rat brain by peptides: structure activity relationship. 391 46

The pars distalis of the avian adenohypophysis consists of well-defined cephalic and caudal lobes which are distinct in their cellular constituents. Immunocytochemical investigations on the pituitary hormones of the pars distalis of the Japanese quail reveal five types of secretory cells, adenocorticotropin (ACTH) cells, prolactin (PRL) cells, thyroid-stimulating hormone (TSH) cells, growth hormone GH (STH) cells, and FSH/LH (gonadotropic) cells. The ACTH cells, TSH cells, and PRL cells are restricted to the cephalic lobe, and GH (STH) cells are confined to the caudal lobe, while FSH/LH cells are distributed throughout the cephalic and caudal lobes. The median eminence of birds has distinct anterior and posterior divisions, each with different neuronal components. The avian hypophysial portal vessels also consists of two groups, anterior and posterior. The peculiar arrangement and distribution of the avian hypophysial portal vessels are possibly related to the distribution of neuropeptides in the two divisions of the median eminence and to the cytological and functional differentiation of two lobes of the pars distalis. The localization of perikarya and fibers containing luteinizing hormone releasing hormone (LHRH), somatostatin, vasotocin, mesotocin, corticotropin-releasing factor (CRF), vasoactive intestinal polypeptide (VIP), glucagon, metenkephalin, and substance P in the hypothalamus and median eminence of the Japanese quail has been investigated by means of immunohistochemistry using antisera against the respective neuropeptides. LHRH-, somatostatin-, VIP-, met-enkephalin-, and substance P-immunoreactive fibers are localized in the external layer of the anterior and posterior divisions of the median eminence, while CRF- and vasotocin-reactive fibers are demonstrated only in the external layer of the anterior division of the median eminence. The metenkephalin fibers are thicker in the anterior median eminence but the substance P fibers are more abundant in the posterior division. Mesotocin fibers occur only in the internal layer of the median eminence and neural lobe.
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PMID:Immunohistochemistry of the hypothalamic neuropeptides and anterior pituitary cells in the Japanese quail. 608 43

AtT20/D16v is a clonal strain of mouse pituitary tumor cells which synthesizes and secretes ACTH. Somatostatin, a hypothalamic tetradecapeptide, has been shown to inhibit the release of PRL, GH, and TSH from the pituitary gland. We have characterized specific binding sites for somatostatin on AtT20/D16v cells and demonstrate that somatostatin inhibits stimulated ACTH release by these cells. Equilibrium binding studies with [125I]Tyr1]somatostatin showed the presence of a single class of noninteracting binding sites on AtT20/D16v cells. Half-maximal binding of somatostatin occurred at 1.7 X 10(-9) M, and there were 26,300 binding sites/cell. The binding of [125I]Tyr1]somatostatin was not significantly inhibited by the hypothalamic peptides TRH, LHRH, and substance P. Somatostatin had no consistent effect on basal ACTH secretion by AtT20/D16v cells, but it inhibited ACTH secretion stimulated with either 50 mM KCl or a hypothalamic extract. Half-maximal inhibition occurred with 4 X 10(-10) M somatostatin. TRH, LHRH, and substance P at concentrations of 10(-7) M were without effect. Somatostatin had no effect on either basal or stimulated hormone secretion by GH12C1 or F4C1 cells, two cell strains which lack specific somatostatin-binding sites. A critical concentration of extracellular calcium was required for the stimulation of ACTH secretion in AtT20/D16v cells. No response to 50 mM KCl occurred in the presence of EGTA or cobalt. Increased extracellular calcium overcame the inhibition of stimulated hormone secretion by EGTA, cobalt, and somatostatin. Therefore, we conclude that the inhibition of stimulated ACTH secretion by somatostatin involves the interaction of the peptide with specific binding sites on AtT20/D16v cells and the inhibition of stimulus-elicited calcium influx.
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PMID:Inhibition of adrenocorticotropin secretion by somatostatin in pituitary cells in culture. 610 20


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