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)

Biologically active peptides and neurotransmitter substances were added to anterior pituitary cell cultures to examine the presence of corticotropin releasing factor (CRF)-like activity. Hypothalamic extract (HE) induced significant dose-related increase of ACTH, and the lowest effective dose was 0.01 HE/ml. Other tested substances including luteinizing hormone-releasing hormone, thyrotropin releasing hormone, melanocyte stimulating hormone release inhibiting factor, somatostatin, substance P, neurotensin, beta-endorphin. leu-enkephalin, met-enkephalin, bradykinin, norepinephrine, dopamine, serotonin, acetylcholine, histamine, gamma-amino butyric acid or gamma-hydroxy butyric acid showed no CRF-like activity. Relatively high doses of lysine vasopressin, arginine vasopressin and angiotensin II increased the release of ACTH in pituitary cell cultures, but the maximal ACTH response was markedly less than with HE. These results indicate that cultured anterior pituitary cells are sensitive and fairly specific in detecting CRF(s) comparing with other detecting procedures.
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PMID:Specificity of cultured anterior pituitary cells in detecting corticotropin releasing factor(s): the effect of biologically active peptides and neurotransmitter substances on ACTH release in pituitary cell cultures. 3 34

Changes in plasma levels of vasoactive peptides during hemodialysis have mainly been attributed to changes in plasma volume and osmolality. This study investigated the effect of the extracorporeal circulation on plasma levels of vasoactive peptides, noradrenaline, and renin. Eleven stable hemodialysis patients were studied during sham dialysis for 60 min using a Cuprophan dialyzer (Alwall GFE11, Gambro AB, Lund, Sweden). With regard to vasoconstrictors, there was an increase in noradrenaline (NA) (13%, p < 0.05) and renin (PRA) (32%, p < 0.05), while arginine vasopressin and neuropeptide Y remained unaltered. Concerning vasodilators, an increase in substance P (SP) (23%, p < 0.05) and vasoactive intestinal peptide (VIP) (15%, p < 0.01) was observed, while a decrease in atrial natriuretic peptide (ANP) (17%, p < 0.05) and motilin (MOT) (24%, p < 0.01) occurred. Calcitonin gene related peptide and beta endorphin were unaltered. A decrease in blood pressure was observed, while heart rate remained unchanged. The authors conclude that the extracorporeal circulation, per se, affects plasma levels of vasoactive substances and influences vascular stability. The decrease in ANP and MOT might be due to adsorption to the dialysis membrane. The increase in some vasoconstrictors (NA, PRA) and vasodilators (SP, VIP) might be induced by the blood-artificial surface contact, or by other factors, e.g., heparin or cooling of the blood during the procedure.
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PMID:Effects of sham hemodialysis on plasma levels of vasoactive peptides in patients with uremia. 128 Oct 14

Certain neuropeptides can facilitate lordosis by acting on midbrain periaqueductal gray (PAG) in estrogen-primed female rats. Here, we investigated responses of individual PAG neurons in vitro, to five neuropeptides: substance P (SP), luteinizing hormone-releasing hormone (LHRH), prolactin (PRL), oxytocin (OT), and thyrotropin-releasing hormone (TRH). Substance P, OT, and TRH excited spontaneous activity of PAG neurons through neurotransmitter-like actions in a dose-dependent manner, whereas LHRH and PRL virtually never affected PAG neurons this way. Oxytocin acted through oxytocin receptors located on the recorded PAG neurons, since excitatory actions of OT were 1) not abolished by synaptic blockade, 2) mimicked by the OT-specific agonist [Thr4, Gly7]OT but not by arginine vasopressin, and 3) blocked by the OT-specific antagonist [d(CH2)5,Tyr(Me)2,Orn8]vasotocin. Although LHRH had no neurotransmitter-like action on spontaneous activity of PAG neurons, it, as well as SP, could modulate responses of some dorsal PAG neurons to GABAA and GABAB agonists or norepinephrine. Neuromodulatory actions of LHRH and SP could help facilitate lordosis through PAG neurons.
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PMID:Effects of lordosis-relevant neuropeptides on midbrain periaqueductal gray neuronal activity in vitro. 128 9

In order to establish possible stimulatory effects of increasing plasma concentrations of substance P (SP) on the arginine vasopressin (AVP) and/or oxytocin (OT) secretion, successively increasing doses of SP(0.5, 1 and 1.5 pmol/kg-1/min-1; each dose for 20 min) were infused in 7 normal men. Plasma AVP and OT levels were measured before infusion and every 20 min, just before increasing the infusion dose of SP. During tests, SP infusion did not produce untoward side effects or changes in blood osmolality and/or pressure. Plasma OT levels did not change during SP infusion. Plasma AVP concentrations were not modified by the infusion of the lowest dose of SP, whereas they were significantly increased in a dose response fashion when higher amounts of SP were given. These findings demonstrate for the first time in humans that the systemic administration of SP exerts stimulatory effects on AVP, but not on OT secretion.
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PMID:Effects of intravenous infusion of substance P on arginine vasopressin and oxytocin secretion in normal men. 137 80

The fasting plasma levels of 10 vasoactive regulatory peptides were measured by radioimmunoassay in 23 stable patients with chronic renal failure receiving regular hemodialysis treatment (RDT) and compared with those of healthy controls. The plasma concentrations of arginine vasopressin, atrial natriuretic peptide, beta-endorphin, methionine-enkephalin, motilin, neuropeptide Y, substance P, and vasoactive intestinal peptide were increased. The plasma level of calcitonin gene-related peptide was not statistically different from that of the controls. The plasma concentration of gamma 2-melanocyte-stimulating hormone was lowered in the RDT-patients. The arterial blood pressure correlated with the plasma levels of motilin and neuropeptide Y. We conclude that patients with chronic renal failure receiving RDT have increased concentrations of 8 out of 10 measured vasoactive regulatory peptides. The elevated levels of vasoactive peptides may contribute to the adaptation of the cardiovascular system to impaired renal function.
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PMID:Plasma levels of vasoactive regulatory peptides in patients receiving regular hemodialysis treatment. 137 31

Immunocytochemical localization of neuropeptides (beta-endorphin, substance P, arginine vasopressin, oxytocin), pituitary hormones (adrenocorticotropin, prolactin, growth hormone, follicle stimulating hormone (FSH), gonadal inhibin, gastrin, and human chorionic gonadotrophin (hCG)) was carried out in marmoset testis during development. Both intensity of immunostaining and distribution of these peptides in testicular compartments viz. seminiferous tubules and Leydig cells changed dramatically during development. In vitro biosynthesis of inhibin and FSH was increased by hCG, whereas prolactin (5 micrograms) and prostatic inhibin peptide suppressed the synthesis of these hormones.
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PMID:Immunocytochemical localization of bioregulatory peptides in marmoset testes. 138 Feb 34

Regularly discharging baroreceptors in a rat in vitro aortic arch preparation were exposed to increasing concentrations of one of four vasoactive peptides: angiotensin II, arginine vasopressin, atrial natriuretic factor, or substance P. Slow ramps of pressure evoked discharge responses in single-fiber baroreceptors. Instantaneous discharge frequency was measured simultaneously with aortic diameter and pressure. During constriction induced by angiotensin II or arginine vasopressin, baroreceptor diameter threshold (Dth) decreased and pressure threshold (Pth) tended to increase; these effects were reduced or eliminated by nitroprusside. Atrial natriuretic factor and substance P by themselves were without effect on vessel diameter or on baroreceptor discharge. In preparations preconstricted with a moderate concentration of phenylephrine (10(-8) M), atrial natriuretic factor reduced the phenylephrine-induced constriction and increased Dth and decreased Pth. Substance P, even at high concentrations, was less effective than atrial natriuretic factor in reducing phenylephrine constriction and in altering baroreceptor discharge. Baroreceptor gain was unaffected by any of these peptides. Thus, changes in smooth muscle tone altered mechanotransduction by shifts in 1) the vessel pressure-diameter relation and 2) baroreceptor threshold requirements (Pth and Dth). Changes in the baroreceptor mechanical threshold (Dth) reduced the effects on Pth expected from changes in vessel wall mechanics. Pth reflects the net effects of vessel wall and Dth changes. Pth generally increased during constrictions and decreased during dilations. The changes in Dth and their selectivity (no changes in gain) during vasoactive peptide action closely resemble rapid resetting of baroreceptors. We propose that vascular smooth muscle lies in a parallel arrangement with aortic baroreceptors and that a common compensatory mechanism regulates Dth during sustained changes in vessel diameter. Activation of smooth muscle and reductions in transmural pressure would reduce loading of baroreceptors, and the proposed compensatory mechanism would tend to keep discharge constant by decreasing Dth. Our experiments, however, cannot distinguish between hypotheses for local micromechanical changes in coupling or for changes modulating excitability within the baroreceptor neuron itself as the basis for Dth adjustments.
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PMID:Peptidergic modulation of mechanotransduction in rat arterial baroreceptors. 168 17

Bacterial lipopolysaccharide (LPS) and corticotropin releasing hormone (CRH) plus arginine vasopressin (AVP) induce immunoassayable (1-13)ACTH (alpha MSH) from mononuclear leukocytes. We studied the ability of LPS and CRH + AVP to in vitro stimulate native ACTH (not alpha MSH) and substance P (SP) production and thymidine incorporation in human mononuclear leukocytes. Neither CRH + AVP nor LPS stimulated detectable amounts of intracellular or extracellular ACTH (less than 15 pg/8 x 10(6) cells or total medium) or SP (less than 50 pg/8 x 10(6) cells or total medium) at 1, 2, 3 or 4 days of incubation. LPS, but not CRF + AVP, increased the amount of 3H-thymidine incorporation over controls. This data questions the importance of an immunoadrenal axis and the synthesis of SP by mononuclear leukocytes.
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PMID:Corticotropin releasing hormone and arginine vasopressin stimulation of ACTH and substance P in human mononuclear leukocytes. 169 18

We have investigated the central effects of substance P (SP) on plasma concentrations of immunoreactive ACTH and on immunoreactive and bioactive arginine vasopressin (AVP) in the rat. The injection of SP (20 nmol) into the lateral ventricle intracerebroventricular, (i.c.v.) of ethanol-anaesthetised rats produced a prolonged antidiuresis lasting at least 30 min, associated with an increase in plasma AVP (from 7.8 +/- 0.6 to 12.5 +/- 1.9 fmol/ml, mean +/- SEM, n = 6). Concentrations of plasma ACTH were significantly decreased 30 min following SP (from 320 +/- 70 to 135 +/- 15 fmol/ml, n = 12). In rats anaesthetised with urethane, a significant decrease in plasma ACTH was observed 15 and 30 min following i.c.v. injection of SP (20 nmol); a downward trend was also observed in ACTH following a 40 nmol dose, but this was not significant. No effect of SP was observed on either basal or CRF-41-stimulated ACTH release from isolated rat anterior pituitary cells in vitro. These results demonstrate for the first time that SP exerts opposite effects upon the release of ACTH and AVP in the same animal, and suggest that these actions occur at the level of the hypothalamus.
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PMID:Substance P stimulates arginine vasopressin and inhibits adrenocorticotropin release in vivo in the rat. 169 61

Cardiovascular responses to intracerebroventricular (icv) injections of substance P and somatostatin were measured in Long-Evans and Brattleboro rats treated with streptozotocin (STZ) or saline. Substance P icv evoked similar pressor responses and tachycardia in STZ-treated and saline-treated Long-Evans rats, together with signs of behavioral activation (i.e., arousal). As a group, Brattleboro rats did not respond significantly to icv substance P, although some individual rats showed clear cardiovascular and behavioral responses. These findings may indicate a reduced sensitivity to icv substance P in Brattleboro rats but show no differences attributable to STZ treatment. Hence, diminished pressor responses to icv angiotensin II (observed previously) may be specific to sympathoadrenal activation associated with drinking. Somatostatin caused a pressor effect in saline-treated, but not in STZ-treated, Long-Evans rats, which was probably due to arginine vasopressin (AVP)-mediated mechanisms because it was not present in either saline-treated or STZ-treated Brattleboro rats. Both control and STZ-treated Long-Evans rats showed a bradycardic response to somatostatin that was not seen in Brattleboro rats. These results indicate that different AVP-mediated mechanisms might be responsible for the pressor and bradycardic effects of icv somatostatin. It is possible that impairment of central somatostatin-mediated AVP release contributes to the diminished role of AVP in blood pressure recovery following ganglion blockade in STZ-treated rats described previously.
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PMID:Central effects of substance P and somatostatin in conscious, streptozotocin-treated rats. 169 38


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