Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01178 (oxytocin)
 15,767 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The brain contains a large variety and number of peptides some of which were known earlier as hypothalamic hormones (vasopressin, oxytocin, luteinizing hormone-releasing hormone, thyrotropin-releasing hormone, somatostatin) or as pituitary hormones (the family of opiomelanocortins), while others, not primarily known as hypothalamic or pituitary hormones, may also have endocrine effects (substance P, angiotensin II, neurotensin, bombesin, vasoactive intestinal peptide (VIP), gastrin-cholecystokinin, glucagon, carnosine, bradykinin). These peptides, which form a new class of putative neurotransmitters, are present early in brain development and show important sex differences in both their pattern of innervation and their effects. Their peripheral effects may include intrauterine growth of the placenta and fetus, the timing of birth, acceleration of the course of labour and responses to haemorrhage (redistribution of cardiac output and stimulation of blood cell formation). Endogenous peptides are probably involved in brain development, which may explain their general, permanent and sex-dependent effects when given in the period of rapid brain development. Although peptides might in the future be useful for stimulating recovery from retarded brain development, at present one should be aware of the potential dangers of their use in, for example, obstetrics.
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PMID:Development of peptidergic systems in the rat brain. 627 64

Using a technique for simultaneous visualisation of two antigens in one section, oxytocin-like immunoreactivity has been found to coexist with bombesin-like immunoreactivity in neurons of the basal disk, gastric region and tentacles of hydra. Neurons with oxytocin-like immunoreactivity in peduncle and hypostome, on the other hand, have little or no bombesin-like material. Oxytocin-like immunoreactivity never coexists with FMRFamide-immunoreactivity. The neurons with oxytocin- and FMRFamide-like immunoreactivity, however, are often found to be closely intermingled. The results show that coexistence, as well as non-coexistence, of neuropeptides is a phylogenetically old principle.
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PMID:Coexistence of neuropeptides in hydra. 635 76

Neurohypophyseal hormones and related peptides cause behavioural alterations after intracerebroventricular injection in mice. In the present study, these effects, consisting of excessive grooming and scratching, and of escape-directed activity in stressful situations, could easily be distinguished from those of other centrally acting peptides and drugs by means of two different behavioural bioassays. The effects were not antagonized by drugs that block cholinergic or adrenergic receptors, but they were powerfully suppressed by some potent psychotropic agents. Some compounds with strong vasoconstrictor or vasodilatory actions did not mimick or antagonize the behavioural alterations, suggesting that vasoconstriction is not essential for the induction of these effects. A considerable degree of tolerance could be induced and cross-tolerance was observed between different neurohypophyseal hormones. In rats, behavioural alterations caused by oxytocin and vasopressin could be demonstrated as well, but they were by far less pronounced than those observed in mice. For comparison, some data on the behavioural effects of bombesin are included. This peptide caused behavioural alterations similar to those of the neurohypophyseal hormones, but these were apparently mediated by different mechanisms. It is suggested that centrally-released oxytocin and/or vasopressin might be physiologically involved in the regulation of animal behaviour.
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PMID:Short-term behavioural effects of neurohypophyseal hormones: pharmacological characteristics. 708 65

In an earlier study we have shown that local application of capsaicin directly to one sciatic nerve induces a decrease of substance P and cholecystokinin octapeptide (CCK8)-like peptide from the dorsal spinal cord using immunocytochemical analysis. Here the effect of locally applied capsaicin on seven peptides known to be present in the L4 segment was assessed by radioimmunoassay and immunocytochemistry. The peptides investigated were substance P, somatostatin and CCK8-like peptide (which are present in small diameter primary afferent fibres), neurotensin, enkephalin (which are intrinsic to the spinal cord), neurophysin (of supraspinal origin) and bombesin (whose origin is unknown). Fourteen days after a single application of 49 mM solution of capsaicin a significant depletion of substance P and somatostatin was detected. These results were confirmed by parallel immunocytochemical analysis which localised the dramatic decreases of substance P and somatostatin to lamina 1 and lamina 2. In addition a depletion of CCK8-like immunoreactivity was observed by immunocytochemistry in this area, but quantitative radioimmunoassay of CCK8-like peptide did not detect this depletion. The capsaicin-induced changes were dose-dependent and reversible. Small decreases were noted with concentrations of capsaicin as low as 0.1 mM. The changes were apparent from day 9 onwards, maximal depletion seen by day 14. By 200 days post-operatively, a recovery to normal peptide levels in the ipsilateral dorsal horn was observed. In addition, a significant depletion of cutaneous substance P was noted in the area of the skin innervated by the capsaicin-treated nerve. These changes were accompanied by a significant increase in noxious thermal response (hind paw immersion test, T = 49 degrees C, ipsilateral leg 9.11 +/- 1.3 seconds, contralateral leg: 5.1 +/- 1.3 seconds, P = less than 0.005). The peptides neurotensin, enkephalin, neurophysin and bombesin were not affected by capsaicin treatment. These findings suggest that local application of capsaicin induces an indiscriminate depletion of peptide-containing primary sensory afferent fibres which is dose-dependent, long-lasting, but reversible.
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PMID:Local application of capsaicin to one sciatic nerve of the adult rat induces a marked depletion in the peptide content of the lumbar dorsal horn. 716 30

The actions of various peptides were studied using isolated spinal cord preparation of newborn rat. Vasopressin, substance P, thyrotropin releasing hormone, bombesin, gastrin releasing peptide, oxytocin, neurotensin, cholecystokinin-octapeptide and angiotensin II produced marked depolarizing responses of motoneurons with threshold concentrations of 5 X 10(-10)--8 X 10(-9) M. After the elimination of transsynaptic action by tetrodotoxin, the actions of these peptides were depressed to various extents, the former 5 peptides producing relatively large responses. Somatostatin and enkephalin depressed the dorsal root potential and produced slight hyperpolarization of dorsal root fibers. It is suggested that many of these peptides play important roles in synaptic transmission in mammalian spinal cord.
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PMID:Actions of vasopressin, gastrin releasing peptide and other peptides on neurons on newborn rat spinal cord in vitro. 730 Dec 1

Because of the enormous growth over the last three decades of research on the role of peptides in the brain, the need became apparent to determine the status of these compounds in terms of their current research interest. Since 1965, over a quarter of a million research papers have been published on peptides that have since been classified as neuroactive. The present study was undertaken to analyze systematically the yearly trends of research emphasis in neuroactive peptides as reflected by their individual frequency of publication by year, beginning in 1966. A computer analysis of the publication characteristics was carried out using the Medline data base in which the citation search was limited to the topic brain crossed with the topic mammal. One criterion for the inclusion of a given peptide in the analysis was a frequency of 25 or more citations following its discovery, as related to the mammalian brain. The 42 peptides that met this criterion were: adrenocorticotropic hormone, angiotensin II, atrial natriuretic factor, bombesin, bradykinin, calcitonin, calcitonin gene-related peptide, carnosine, beta-casomorphin, cholecystokinin, corticotropin-releasing factor, delta sleep-inducing peptide, dynorphin, beta-endorphin, Leu-enkephalin, Met-enkephalin, galanin, gastrin, glucagon, growth hormone, growth hormone-releasing factor, insulin, kyotorphin, beta-lipotropin, luteinizing hormone-releasing factor, melanocyte-stimulating hormone release inhibitory factor-1, alpha-melanocyte-stimulating hormone, motilin, neurokinin A, neurokinin B, neuropeptide Y, neurotensin, oxytocin, pituitary adenylate cyclase activating polypeptide, peptide HI, prolactin, secretin, somatostatin, substance P, thyroid-releasing hormone, vasopressin, and vasoactive intestinal peptide. An overall analysis of the 298,105 papers published on these 42 peptides since 1965 revealed that the research activity of 24,742, or 8.30%, of the studies, focused on their neuroactive properties. Taken as a whole, the research on neuroactive peptides reached a peak in 1986, as reflected by the total of 1793 papers published during that year. Although the level of publication has fluctuated between 1548 and 1774 research papers over the last 6 years, it is now clear that the trend in research on neuroactive peptides has reached an asymptote today that shows no sign of deviation. A temporal analysis year by year of individual publication profiles revealed three distinct trends: 1) peptides showed a slow development in research interest and did not exceed more than 15-30 publications per year; 2) peptides exhibited a steady increase in research activity over the years that continues today; and 3) peptides displayed an initial, often intense, research emphasis that inexplicably declined, in some cases precipitously, in the mid 1980s.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Neuroactive peptides: unique phases in research on mammalian brain over three decades. 800 41

Current data on the influence of neuropeptides on the growth, structure and function of cells comprising the hypothalamo-pituitary-adrenal axis were presented and discussed. The action of vasopressin, oxytocin, neurotensin, bombesin, neuropeptide Y, substance P and VIP have been evaluated. The hypothesis has been introduced that in vivo effect of some neuropeptides on the structure and function of the adrenal cortex is mediated by vasopressin.
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PMID:Involvement of neuropeptides in the regulation of growth, structure and function of the adrenal cortex. 844 30

We investigated the activity of phospholipase D (PLD) in human amnion cells labeled with [3H]oleate. The PLD activity was detected as signal-induced synthesis of phosphatidic acid (PA) and in the presence of ethanol, phosphatidylethanol (PEt). The PLD was shown to be activated by phorbol, 12-myristate, 13-acetate (PMA), calcium ionophore A23187, oxytocin, bombesin and bradykinin, but not by platelet-activating factor (PAF) and epidermal growth factor (EGF). The amniotic PLD thus appeared to be activated by a variety of agonists but with a certain specificity to stimulators. We examined the mode of the PLD activation using PMA (20 nM) and bradykinin (1 microM) as model stimulators. PMA and bradykinin elicited a rapid and sustained response with the peaks of PA-labeling attained at 5 and < 1 min after stimulation, respectively. In both cases, there was a concomitant rise of diacylglycerol (DG), and the PA accumulation was suppressed by ethanol at the expense of labeling of PEt. The PA synthesis caused by the two stimulators was similarly inhibited by staurosporine and by a chronic treatment with PMA (100 nM for 24 h), suggesting that the activation of PLD is linked to the action of protein kinase C. With the cells labeled with radioactive choline and ethanolamine, we found that the amniotic PLD hydrolyzed almost equally phosphatidylcholine and phosphatidylethanolamine. Although bradykinin and PMA stimulated cellular PLD to a comparable extent, prostaglandin (PG)E2 release was not stimulated by bradykinin in contrast to the marked effect by PMA. Further work is thus needed to clarify the significance of the novel PLD signaling pathway in the function of amnion cells.
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PMID:Phospholipase D activity of human amnion cells stimulated with phorbol ester and bradykinin. 850 57

Melanophore pigment dispersion is a sensitive bioassay for activation of the adenylyl cyclase and phospholipase C second-messenger pathways. The necessity of protein kinase activation in causing pigment dispersion was confirmed for eight agonists of endogenous melanophore receptors and for two transfected receptors. All agonists and receptors previously shown to elevate intracellular cAMP in melanophores--melanocyte stimulating hormone, light, (-) norepinephrine, 5-hydroxytrptamine, and the beta2-adrenergic receptor--were able to stimulate pigment dispersion in the presence of Ro31-8220, a potent inhibitor of protein kinase C, but were blocked in the presence of H89, an inhibitor of cAMP-dependent protein kinase. The bombesin receptor, which elevates intracellular IP3 in melanophores, was unable to stimulate pigment dispersion in the presence of Ro31-8220 or H89. Agonists whose mechanism of activation of pigment dispersion are unknown were also tested. Endothelin 3 responses were blocked by both H89 and Ro31-8220, predicting coupling to phospholipase C. Vasoactive intestinal polypeptide, oxytocin, and calcitonin gene-related peptide beta responses were blocked only by H89, predicting coupling to adenylyl cyclase.
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PMID:Melanophore pigment dispersion responses to agonists show two patterns of sensitivity to inhibitors of cAMP-dependent protein kinase and protein kinase C. 869 26

Oxytocin (OX) and bombesin (BN) can both suppress food intake in adult rats. In light of important transient fluctuations in peptide and/or receptor expression early after birth, this study characterized the feeding-suppressant effects of OX and BN during early development and explored their physiological relevance, using BN or OX antagonists, [D-Phe6,des-Met6-14]BN(6-14), ethyl amide (des-Met), and [des-Glycinamide9,d(CH2)5',O-Me-Tyr2,Thr4,Orn8]-vaso toc in (vasotocin), respectively. On postnatal days (PD) 1, 5, 10, and 15, groups of food-deprived Sprague-Dawley rat pups (n = 8-11) were injected SC with saline (control) or BN (0.6, 0.06, or 0.006 mg/kg), des-Met (10 mg/kg), OX (1.2, 0.6, 0.3, or 0.15 mg/kg), or vasotocin (1.0 mg/kg), and their intake of milk (from a piece of absorbent paper saturated with warm milk) was monitored. Results revealed that BN and OX suppressed milk intake from PD 1 to PD 15. Although the milk intake varied with the peptide dose, this effect was age dependent. The doses of BN (but not OX) required to suppress feeding were higher than those needed in adults. When administered alone, OX or BN antagonists did not affect food intake, except at PD 15 for des-Met and PD 1 and PD 10 for vasotocin, where they enhanced feeding. These results suggest that pharmacological effects to OX and BN are apparent from hours after birth and that these peptides may play a role in the regulation of ingestive behavior from early on in ontogeny.
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PMID:Pharmaco-ontogenic modulation of feeding by oxytocin, bombesin, and their antagonists. 895 45


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