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 review deals with the critical analysis of the recent publications showing an important role of the endothelium in the mechanism of vasodilation caused by endogenous agents (acetylcholine, bradykinin, substance P, ATP, histamine, thrombin) and pharmacological agents (clonidine, hydralazine, mellitin, calcium ionophore A 23187). The mechanism of the endothelium-dependent vasodilatation is based on the release of the endothelium-derived relaxant factor (EDRF). In 1987-1988 it was shown that in some cases EDRF is NO. The experimental evidence suggests that EDRF (NO) may directly activate guanylate cyclase that results in vascular smooth muscle relaxation due to cAMP accumulation. The possible physiological and pathophysiological significance of the endothelium-dependent vascular responses is discussed.
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PMID:[The pharmacology of endothelium-dependent vascular reactions]. 285 Feb 22

A large number and variety of compounds (acetylcholine, adenosine diphosphate, adenosine triphosphate, arachidonic acid, bradykinin, Ca2+ ionophores, calcitonin gene-related peptide, histamine, hydralazine, substance P, thrombin, and vasoactive intestinal polypeptide) have been shown to relax arterial smooth muscle indirectly. The endothelium in muscular arteries from several species appears to have receptors for these vasodilators. Binding of one of these compounds to its endothelial receptors results in the release (and presumably synthesis) of substance(s) that act on arterial smooth muscle to cause relaxation. The name endothelium-derived relaxing factor (EDRF) has been proposed for the substance or substances responsible for inhibition of contraction. Studies to determine additivity of endothelium-dependent relaxing agents and sensitivity of EDRF-mediated responses to a variety of inhibitors suggest that a single factor or a single common mechanism induces relaxation of vascular smooth muscle. Pharmacological studies have been equivocal with regard to the postulated involvement of phospholipases or arachidonic acid and to the suggestion that EDRF is an oxidative, non-cyclooxygenase product of arachidonate. Experiments on transfer of EDRF and reversal of endothelium-dependent relaxation consistently indicate that EDRF is quite labile. There is convincing evidence that EDRF activates smooth muscle guanylate cyclase, which results in an increase in intracellular cyclic guanosine 3',5'-monophosphate levels. The stimulation of guanylate cyclase by EDRF provides a valuable and sensitive parameter for studies with arteries as well as cells in culture. At present, the identity of EDRF and its role in cardiovascular homeostasis are unknown.
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PMID:Endothelium-derived vascular relaxing factor. 298 29

In the last few years, experimental evidence has accumulated which suggests a substantial role for the endothelium in the control of vascular tone. Endothelium-dependent dilatations have been demonstrated in various arteries of numerous mammalian species including man. Among the stimuli which elicit endothelium-dependent dilatation are such varying stimuli as increases in blood flow and hypoxia, as well as endogenous (acetylcholine, ATP, ADP, bradykinin, substance P) and pharmacological agents (calcium ionophore A 23187, ergometrine, hydralazine, melittin). The functional importance of endothelium-dependent dilatation is emphasized by the fact that the direct vasoconstrictor effects of some of these substances (acetylcholine, histamine, norepinephrine, serotonin) on vascular smooth muscle is attenuated or even reversed by their simultaneous stimulatory effect on endothelial cells, resulting in the release of a vasodilator signal. Bioassay experiments have shown that a humoral vasodilator agent with a biological half-life in the range of seconds is released from the endothelium (native or cultured) during stimulation with acetylcholine, ATP and calcium ionophore. Experimental data are presented, which suggest that EDRF may act by direct stimulation of guanylate cyclase, resulting in smooth muscle relaxation due to increased smooth muscle cyclic GMP levels. The chemical nature of this nonprostaglandin endothelium-derived relaxant factor (EDRF) is still not known. The possible physiological and pathophysiological significance of endothelium-dependent dilatation in situ is discussed. Special attention is paid in this context to the potential role of EDRF activity in coronary vasomotor control.
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PMID:The role of endothelium in the control of vascular tone. 300 Mar 43

In the last few years, experimental evidence has accumulated which suggests a substantial role for the endothelium in the control of vascular tone. Endothelium-dependent dilations have been demonstrated in various arteries of numerous mammalian species including man. Among the stimuli which elicit endothelium-dependent dilatation are such different stimuli as increases in blood flow and hypoxia as well as endogenous (acetylcholine, ATP, ADP, bradykinin, substance P) and pharmacological agents (calcium ionophore A 23 187, ergometrine, hydralazine, melittin). The functional importance of endothelium-dependent dilatation is emphasized by the fact that the direct vasoconstrictor effects of some of these substances (acetylcholine, histamine, norepinephrine, serotonin) on vascular smooth muscle is attenuated or even reversed by their simultaneous stimulatory effect on endothelial cells resulting in the release of a vasodilator signal. Bioassay experiments have shown that a humoral vasodilator agent with a biological half-life in the range of seconds is released from the endothelium (native or cultured) during stimulation with acetylcholine, ATP and calcium ionophore. Experimental data are presented which suggest that EDRF may act by direct stimulation of guanylate cyclase, resulting in smooth muscle relaxation due to increased smooth muscle cyclic GMP levels. The chemical nature of this nonprostaglandin endothelium-derived relaxant factor (EDRF) is still not known. The possible physiological and pathophysiological significance of endothelium-dependent dilatation in situ is discussed. Special attention is paid in this context to the potential role of EDRF activity in coronary vasomotor control.
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PMID:[Regulation of vascular tone by the endothelium]. 300 57

A brief review is first presented of findings during the past few years by the authors and by others on the nonprostaglandin endothelium-dependent relaxation of isolated arteries by a large number of vasoactive agents. Among these agents are acetylcholine (ACh); the calcium ionophore A23187; ATP and ADP; substance P; bradykinin (canine, human, and porcine arteries); histamine, acting via an H1-receptor (rat arteries); thrombin (canine arteries); serotonin (canine coronary artery); and norepinephrine, acting via an alpha2-receptor (canine coronary artery). The endothelium-derived relaxing factor (EDRF) released by ACh and other agents has not yet been identified. Our original hypothesis that arachidonic acid is the precursor of EDRF is not supported by the finding that other unsaturated fatty acids in addition to arachidonic acid, and even stearic acid, elicited nonprostaglandin endothelium-dependent relaxations. Methylene blue and hemoglobin (but not methemoglobin) rapidly inhibited relaxation of rabbit aorta by ACh or A23187, suggesting that our proposal that EDRF is a labile free radical may be correct. The endothelium-dependent relaxation by each of these agents was shown to be preceded by an endothelium-dependent increase in cyclic GMP in the smooth muscle--a finding consistent with the hypothesis that EDRF stimulates guanylate cyclase in the muscle, leading to an increase in cyclic GMP that somehow activates relaxation. Some questions relating to the potential physiological important of endothelium-dependent relaxations are discussed.
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PMID:Endothelial cells as mediators of vasodilation of arteries. 620 42

As atrial natriuretic factor (ANF) is intimately involved in water and electrolyte homeostasis, dose-response studies were performed in the parotid as well as submaxillary glands of the rat with increasing doses of the atrial peptide to investigate its possible role as a sialogogic agent. Dose-response studies were also performed in both salivary glands with different pharmacological agonists known to cause salivation in the rat (methacholine, noradrenaline, isoproterenol, methoxamine and substance P) in the absence and in the presence of ANF. The atrial factor did not induce salivation 'per se' at least in the investigated doses. However, it enhanced the salivary response to methacholine, methoxamine and substance P but it did not modify the salivation induced either by noradrenaline or isoproterenol. The present results showed that ANF enhanced the salivation induced by pharmacological agents which stimulate phosphatidylinositol hydrolysis. These effects of ANF may be probably related to the activation of the non-guanylate cyclase coupled receptor which has been associated with phosphatidylinositol turnover. Nevertheless, although the atrial factor induces vasorelaxation, its enhancement of blood flow may not be the major event underlying the present results. The present work suggests a potential physiological role of ANF on the modulation of salivary secretion and provides further evidence on the rol of ANF in the regulation of body fluid homeostasis.
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PMID:Atrial natriuretic factor enhances induced salivary secretion in the rat. 751 Dec 49

The results of behavioral studies suggest that nitric oxide (NO) participates in certain spinal mechanisms that contribute to hyperalgesia. Additionally, previous studies indicate that the release of immunoreactive calcitonin gene-related peptide (iCGRP) and substance P (iSP) is increased in the dorsal horn of the spinal cord during hyperalgesia. Therefore, the aim of this study was to determine whether NO acts to enhance peptide release in the dorsal horn of rats using an in vitro superfusion technique. Sodium nitroprusside (SNP) was used as an NO donor. The results of this study indicate that SNP caused a dose-related, calcium-dependent increase in the release of iCGRP and iSP from dorsal horn slices of the rat spinal cord. Furthermore, pretreatment with SNP reduced the ability of capsaicin to evoke the release of either peptide, suggesting that a target for SNP exists on certain capsaicin-sensitive primary afferent terminals. In addition to increasing peptide release, SNP also caused a significant five to sixfold increase in the levels of immunoreactive guanosine 3',5'-monophosphate (i-cGMP) in the dorsal horn. This SNP-evoked increase was significantly decreased by the guanylate cyclase inhibitor methylene blue in a dose-dependent manner. In addition, the release of iCGRP was also significantly reduced in the presence of methylene blue, although the relationship between peptide release and i-cGMP production remains unclear. Sodium nitroprusside-evoked peptide release was significantly reduced in the presence of hemoglobin (an oxide radical scavenger), suggesting that the drug effect was due to the generation of NO. However, the release of iCGRP and iSP was also evoked by sodium ferricyanide (the coproduct of SNP) and by 7-d-old, photoinactivated SNP.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Sodium nitroprusside evokes the release of immunoreactive calcitonin gene-related peptide and substance P from dorsal horn slices via nitric oxide-dependent and nitric oxide-independent mechanisms. 751 95

1. Isolated segments of porcine vena cordis magna exhibited a reproducible contractile activity upon application of prostaglandin F2 alpha (PGF2 alpha) or KCl, that was independent of the presence of intact endothelium. Substance P (3 nM) elicited strictly endothelium-dependent relaxations amounting to 46.1 +/- 1.4% (n = 206) of contractions induced by 10 microM PGF2 alpha. 2. S-nitroso-N-acetyl-D,L-penicillamine (SNAP), a compound that spontaneously liberates nitric oxide, concentration-dependently relaxed PGF2 alpha-precontracted (50 microM) venous segments. Tolerance induction (incubation with 100 microM SNAP for 30 min) within the same segments resulted in a 3 fold attenuation of this effect, which was not further reduced after additional preincubation with glyceryl trinitrate (GTN). Removal of endothelium or the presence of N omega-nitro-L-arginine methylester (L-NAME) significantly improved the potency of SNAP before and after tolerance induction. 3. Concentration-dependent relaxations induced by GTN in non-tolerant veins were similar in the presence and absence of endothelium but much more reduced in tolerant endothelium-denuded (75 fold) compared to intact (20 fold) segments. In contrast, the presence of L-NAME significantly improved GTN-activity solely in non-tolerant veins, which, therefore, also resulted in a more pronounced attenuation of activity due to tolerance induction (100 fold). Preincubation of intact veins with SNAP also reduced GTN-activity but to a lesser extent (10 fold). 4. The more delayed but much longer, and compared to GTN somewhat weaker, acting new nitrovasodilator N-(3-nitrato-pivaloyl)-1-cysteineethylester (SPM 3672) was more potent in denuded than intact non-tolerant venous segments. Induction of tolerance by GTN resulted in a 2 fold-attenuation of potency. This effect was increased to 15 fold in denuded veins but solely due to enhanced potency of SPM 3672 caused by removal of endothelium.5. These data demonstrate that intact endothelium of porcine vena cordis magna attenuates the relaxant potency of nitrovasodilators but also probably participates in vascular bioactivation of GTN.We suggest that the reduced potency of nitrovasodilators is due to endogenous production of nitricoxide, which may affect the soluble guanylate cyclase/cyclic GMP-system or inhibit nitrate bioactivation pathways.
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PMID:Nitrovasodilator-induced relaxation and tolerance development in porcine vena cordis magna: dependence on intact endothelium. 752 Dec 58

The present investigation describes the antinociceptive effect of capsaicin in the acetic acid-induced abdominal stretch assay and its mediation by substance P(1-7) fragment [SP(1-7)] and nitric oxide (NO). When injected intrathecally 24 hr before testing, SP(1-7) produced a dose-related decrease in the number of abdominal stretches induced by an i.p. injection of acetic acid. The antinociceptive effect of SP(1-7) (10 nmol) persisted for 62 hr after its injection, a time course that was similar to that produced by a dose of capsaicin (2.6 nmol) that produced an effect of similar magnitude. Antinociception induced by 10 nmol of SP(1-7) was completely reversed by coadministration of 10 nmol of D-SP(1-7); the equivalent antinociception produced by capsaicin was reversed by as small a dose as 1 nmol of D-SP(1-7). The guanylate cyclase inhibitor, methylene blue, at a dose of 10 nmol, prevented both SP(1-7)- and capsaicin-induced antinociception. Capsaicin-induced, but not SP(1-7)-induced, antinociception was prevented by Nw-nitro-L-arginine methyl ester, an NO synthase inhibitor. This inhibition of capsaicin was reversed by coadministration of 120 nmol of L-arginine. Reduced hemoglobin did not prevent capsaicin-induced antinociception. These findings suggest NO is produced and acts within capsaicin-sensitive primary afferent fibers in the dorsal spinal cord to mobilize substance P, resulting in N-terminal induced-antinociception.
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PMID:Substance P N-terminal metabolites and nitric oxide mediate capsaicin-induced antinociception in the adult mouse. 752 54

Nitric oxide synthase-containing cells were visualized in the anterior pituitary gland by immunocytochemistry. Consequently, we began an evaluation of the possible role of NO in the control of anterior pituitary function. Prolactin is normally under inhibitory hypothalamic control, and in vitro the gland secretes large quantities of the hormone. When hemipituitaries were incubated for 30 min in the presence of sodium nitroprusside, a releaser of NO, prolactin release was inhibited. This suppression was completely blocked by the scavenger of NO, hemoglobin. Analogs of arginine, such as NG-monomethyl-L-arginine (NMMA, where NG is the terminal guanidino nitrogen) and nitroarginine methyl ester, inhibit NO synthase. Incubation of hemipituitaries with either of these compounds significantly increased prolactin release. Since in other tissues most of the actions of NO are mediated by activation of soluble guanylate cyclase with the formation of cyclic GMP, we evaluated the effects of cyclic GMP on prolactin release. Cyclic GMP (10 mM) produced an approximately 40% reduction in prolactin release. Prolactin release in vivo and in vitro can be stimulated by several peptides, which include vasoactive intestinal polypeptide and substance P. Consequently, we evaluated the possible role of NO in these stimulations by incubating the glands in the presence of either of these peptides alone or in combination with NMMA. In the case of vasoactive intestinal polypeptide, the significant stimulation of prolactin release was augmented by NMMA to give an additive effect. In the case of substance P, there was a smaller but significant release of prolactin that was not significantly augmented by NMMA. We conclude that NO has little effect on the stimulatory action of these two peptides on prolactin release. Dopamine (0.1 microM), an inhibitor of prolactin release, reduced prolactin release, and this inhibitory action was significantly blocked by either hemoglobin (20 micrograms/ml) or NMMA and was completely blocked by 1 mM nitroarginine methyl ester. Atrial natriuretic factor at 1 microM also reduced prolactin release, and its action was completely blocked by NMMA. In contrast to these results with prolactin, luteinizing hormone (LH) was measured in the same medium in which the effect of nitroprusside was tested on prolactin release, there was no effect of nitroprusside, hemoglobin, or the combination of nitroprusside and hemoglobin on luteinizing hormone release. Therefore, in contrast to its inhibitory action on prolactin release NO had no effect on luteinizing hormone release. Immunocytochemical studies by others have shown that NO synthase is present in the folliculostellate cells and also the gonadotrophs of the pituitary gland. We conclude that NO produced by either of these cell types may diffuse to the lactotropes, where it can inhibit prolactin release. NO appears to play little role in the prolactin-releasing action of vasoactive intestinal polypeptide and substance P, but mediates the prolactin-inhibiting activity of dopamine and atrial natriuretic factor.
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PMID:Role of nitric oxide in control of prolactin release by the adenohypophysis. 752 11


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