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 Km and Vmax values were determined for enzymes in human lumbar cerebrospinal fluid (CSF) that inactivate synthetic substance P (SP = RPKPQQFFGLM-NH2) and produce metabolic products. For the human lumbar CSF samples analyzed in this study, Km = 2.24 +/- 0.93 mM and Vmax = 0.113 +/- 0.035 nmol/ml/min (n = 10; mean +/- SEM) for the rate of decrease of SP. HPLC analysis of the incubated synthetic peptide fragments demonstrated that the primary enzymatically produced fragment is SP(3-11), with minor amounts in decreasing order of SP(1-4), SP(1-7), and SP(1-9). Electrospray ionization mass spectrometry (ESI-MS) confirmed the appropriate molecular weights for the four peptides, SP(3-11), SP(1-4), SP(1-7), and SP(1-9). These data demonstrate that the primary enzyme in human lumbar CSF that acts on synthetic SP is a post-proline cleaving enzyme (PPCE).
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PMID:Substance P inactivating enzymes in human cerebrospinal fluid. 751 35

OBJECTIVE--To investigate the effects of substance P and papaverine, two drugs that increase coronary blood flow by different mechanisms, on vasomotion in stenotic coronary arteries at percutaneous transluminal coronary angioplasty (PTCA). DESIGN--Coronary blood flow responses to substance P and papaverine were measured in stenotic coronary arteries at the time of PTCA with quantitative angiography and a Doppler flow probe. SETTING--A cardiothoracic referral centre. PATIENTS--15 patients undergoing elective PTCA of a discrete epicardial coronary artery stenosis. INTERVENTIONS--Pharmacological coronary flow reserve was determined with papaverine 5-10 minutes before and after successful PTCA. Endothelium dependent responses to 2 minute infusions of substance P (10-15 pmol.min-1) were assessed immediately before PTCA. MAIN OUTCOME MEASURES--Coronary blood flow responses and changes in epicardial coronary artery area at stenotic, proximal, and distal sites with papaverine and substance P. RESULTS--Stenotic sites dilated with papaverine before PTCA (17.7%(6.9%) (mean (SEM)) area increase, p < 0.05 v baseline). Substance P dilated stenotic sites (16.8%(5.7%) area increase, p < 0.05) and proximal (14.3%(5.4%), p < 0.05) and distal sites (41.7%(9.3%), p < 0.005). Coronary flow reserve increased but did not reach normal values after PTCA (2.3(0.4) before PTCA v 3.0(0.4) after PTCA, p < 0.05) and was associated with an increase in peak flow with papaverine. Angioplasty did not alter baseline flow. After PTCA papaverine caused significant vasoconstriction at the stenotic site (-13.6%(4.3%) area decrease, p < 0.05). There was a negative correlation (r = -0.68, p < 0.05) between the dilator response with papaverine before PTCA and the constrictor response after PTCA. CONCLUSIONS--Substance P causes endothelium dependent dilatation in atheromatous coronary arteries, even at sites of overt atheroma. The cause of the paradoxical constrictor response to papaverine after PTCA is uncertain, but unopposed flow mediated vasoconstriction (the myogenic response) after balloon induced endothelial denudation may be one of several contributory factors.
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PMID:Endothelium dependent and independent responses in coronary artery disease measured at angioplasty. 751 87

Serine proteinases participate in many inflammatory events in the airway. We therefore screened perfusates of isolated rat tracheas for tryptic, elastolytic, and chymotryptic serine proteinases. Only chymotryptic activity, indicated by hydrolysis of the synthetic substrate N-succinylalanylalanylprolylphenylalanyl p-nitroaniline (AAPF), was consistently detected in these perfusates. Basal levels of chymotryptic activity were not increased significantly by electrical field stimulation (EFS) (mean change +/- SEM: -0.05 +/- 0.05 m o.d. units, n = 4) or by 10(-7) M substance P (SP) (+0.04 +/- 0.02 m o.d. units, n = 14). However, the mean change after the stimuli were jointly administered (0.17 +/- 0.06 m o.d. units, n = 12) was significantly greater than control or after EFS (P = 0.01, one-way ANOVA). The SP + EFS-induced chymotryptic activity was inhibited by PMSF, soybean trypsin inhibitor, and chymostatin and was associated with an increase in histamine concentration and immunoreactivity to rat mast cell proteases (RMCP), indicating that the activity is due to mast cell degranulation. However, the activity was not significantly decreased by pretreating rats with systemic compound 48/80. SP + EFS-induced chymotryptic activity peaked rapidly and was associated with modest histamine release and an immediate peak in immunoreactivity to RMCP II, a marker of mucosal mast cells. Immunoreactivity to RMCP I, a marker of connective tissue mast cells, also increased after SP + EFS, but this immunoreactivity was either delayed or more sustained and did not coincide with the peak of chymotryptic activity.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Chymotryptic activity in perfusates of isolated rat trachea: correlation with mucosal and connective tissue mast cell secretion. 752 16

Nonadrenergic noncholinergic nerve fibers supposedly modulate basal coronary flow by releasing capsaicin-sensitive neuropeptides, but the physiological effects of this intrinsic action have not been clarified. We investigated the intrinsic function of nonadrenergic noncholinergic innervation in modulating basal coronary flow in rats. We administered capsaicin to 44 rats to deplete neuropeptides such as calcitonin gene-related peptide (CGRP) and substance P and administered inert vehicle to 60 control rats. Four days later, we measured the coronary pressure-flow relation in the basal state and during maximal coronary vasodilation induced by intracoronary adenosine administration using Langendorff's method. Changes in basal coronary flow prompted by intracoronary infusion of CGRP or substance P and their antagonists were measured in 54 and 30 rats, respectively. Capsaicin-treated rats showed a 31.5 +/- 0.9% (mean +/- SEM) reduction (P < .01) of basal coronary flow in the range of perfusion pressures between 60 and 140 mm Hg compared with untreated control rats, but the maximal coronary flow after adenosine was similar between the two groups. Although basal coronary flow was reduced in capsaicin-treated hearts, left ventricular contractile force and myocardial oxygen consumption did not fall significantly. CGRP increased the coronary flow, but substance P did not. CGRP(8-37), a CGRP receptor antagonist, reduced basal coronary flow by 24.5 +/- 2.1% (P < .01), but FK888, a substance P antagonist, had little effect on it. Thus, capsaicin-sensitive neuropeptides in the rat heart modulate basal coronary flow, providing approximately 30% of it.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Nonadrenergic noncholinergic nerves regulate basal coronary flow via release of capsaicin-sensitive neuropeptides in the rat heart. 752 88

Age-matched male New Zealand white rabbits (n = 16) were allocated to two groups: group 1 (n = 8) received a standard rabbit diet; group 2 (n = 8) received a 2% cholesterol-enriched diet. After 8 weeks of prescribed diet, hearts were excised and placed on a constant perfusion pressure Langendorff-type apparatus. Coronary flow, left ventricular pressure, and isovolumic dP/dt were continuously measured. Baseline recordings were made and then a single 5 nmol bolus dose of substance P was delivered into the coronary perfusate. Mean serum cholesterol levels in group 1 were 53 +/- 17 (SEM) mg.dl-1, in group 2 1438 +/- 143 mg.dl-1. In group 1, the injection of substance P caused mean coronary flow to increase 39 +/- 6%, mean coronary vascular resistance to decrease 28 +/- 3%, and mean dP/dt to increase 11 +/- 4%. In group 2, coronary flow increased 57 +/- 13%, coronary vascular resistance decreased 33 +/- 5%, and dP/dt increased 17 +/- 4%. Within groups, values changed significantly from baseline but these changes were not significantly different between groups. The duration of coronary flow response was 113 +/- 20 s in group 1 and 63 +/- 8 s in group 2. Substance P is a potent dilator of coronary resistance vessels and has positive inotropic effects in the rabbit. High levels of cholesterol exposure do not alter the magnitude of substance P-induced vasodilation, but the duration of the response is shortened.
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PMID:Coronary vascular and myocardial effects of substance P in hypercholesterolemic rabbits. 752 7

Attenuation of the increase in blood flow caused by acetylcholine in the peripheral vasculature and coronary circulation of patients with heart failure has been interpreted as an impairment of endothelium-dependent vasodilation. The aim of this study was to compare in man the effects of acetylcholine, which also has endothelium-independent actions, with substance P, which appears to be a pure endothelium-dependent vasodilator, on epicardial and resistance coronary arteries in patients with idiopathic dilated cardiomyopathy. The effects of intracoronary acetylcholine (10(-7) M and 10(-6) M) and substance P (5, 10 and 25 pmol.min-1) on epicardial coronary artery diameter and coronary blood flow velocity were measured with an intracoronary Doppler flow probe and quantitative coronary angiography in 11 patients with idiopathic dilated cardiomyopathy and 10 control subjects. Epicardial coronary artery diameter did not change with acetylcholine but increased significantly with substance P in both groups (cardiomyopathy patients: 3.3 +/- 0.2 mm (mean +/- SEM) at baseline vs 3.9 +/- 0.2 mm with substance P25 pmol.min-1, P < 0.01; controls: 3.1 +/- 0.2 mm at baseline vs 3.9 +/- 0.3 mm with substance P25 pmol.min-1, P < 0.05). Coronary flow ratios with acetylcholine were lower in cardiomyopathy patients (10(-7) M: 1.4 +/- 0.1 vs 2.3 +/- 0.4, P = 0.05; 10(-6) M: 1.8 +/- 0.2 vs 3.2 +/- 0.5, P = 0.05 vs controls).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:The effects of intracoronary substance P and acetylcholine on coronary blood flow in patients with idiopathic dilated cardiomyopathy. 753 Jun 61

In experimental studies, tachykinins, especially substance P (SP), cause many of the pathophysiological features of neurogenic inflammation. It is unclear whether these peptides are involved in human airway inflammation in diseases such as asthma and chronic bronchitis. To elucidate the relation between neurogenic inflammation and airway inflammatory diseases, we examined the SP concentration in sputum after hypertonic saline inhalation challenge in patients with asthma, patients with chronic bronchitis, and normal volunteers. SP concentration was measured by radioimmunoassay. The sputum SP concentration was significantly higher in patients with asthma (mean +/- SEM, 17.7 +/- 2.4 fmol/ml; p < 0.01) and patients with chronic bronchitis (25.6 +/- 5.5 fmol/ml; p < 0.01) than in normal volunteers (1.1 +/- 0.4 fmol/ml). In patients with asthma, the SP concentration was significantly related to the eosinophil cell count in induced sputum. In all subjects, the SP concentration in induced sputum correlated with FEV1/FVC. These data suggest that neurogenic inflammation may be involved in the airway inflammatory process and subsequent airway narrowing not only in asthma but also in chronic bronchitis.
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PMID:Elevated substance P content in induced sputum from patients with asthma and patients with chronic bronchitis. 753 1

The mitogenic effect of the neuropeptide substance P and bombesin was investigated in normal human keratinocytes in serum-free culture, both with and without the presence of epidermal growth factor (EGF). Although both neuropeptides induced a small increase in cell numbers in the presence of EGF, the response was much greater in its absence, and cell numbers increased to 200% of controls at 5 days. Changes in intracellular free calcium are frequently seen following mitogenic stimulation of cells, and this phenomenon was studied in individual keratinocytes. Epidermal growth factor (10 ng/ml) induced calcium transients in 57% (n = 21) of cells. The mean intracellular free calcium was 97 +/- 11 nM (mean +/- SEM) in quiescent cells, and the calcium transients reached approximately 250 nM for 3-4 min. In the presence of EGF, calcium transients were never observed with the addition of either substance P or bombesin. For EGF-deprived cultures, 20% of keratinocytes (n = 10) showed a large calcium transient following the addition of 500 nM bombesin, and 63% (n = 12) of cells gave calcium transients following the addition of 700 nM of substance P. Studies in calcium-free medium, and following depletion of intracellular calcium stores with thapsigargin, showed that all of the calcium transients were dependent on the presence of intracellular stores, but also partially mediated by an influx of extracellular calcium. These studies demonstrate the mitogenic effect of substance P and bombesin on human keratinocytes in the absence of EGF. The ability of the neuropeptides to increase keratinocyte growth in culture suggests a possible in wound healing.
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PMID:Intracellular calcium as a second messenger following growth stimulation of human keratinocytes. 754 93

"Classical" chemoattractants, such as FMLP, C5a, or leukotriene B4, not only elicit directed motility but also activate neutrophils (degranulation, release of active oxygen species). Signal transduction after ligation of receptors for these classical chemoattractants is mediated by pertussis toxin (PT)-sensitive, heterotrimeric G proteins and the early production of lipid messengers via phospholipases. In contrast, we have previously shown that substance P (SP) and transforming growth factor-beta 1 (TGF-beta 1) are "pure" chemoattractants in that they elicit chemotaxis without activating neutrophils. Paradoxically, pure chemoattractants also activate G proteins (plasmalemmal GTPase activity) without eliciting increments in cytosolic calcium ([Ca]i) and thus inositol trisphosphate. We therefore determined lipid remodeling and signal transduction in response to pure chemoattractants. Increments in plasmalemmal GTPase activated by SP (0.1 microM) and TGF-beta 1 (40 fM), like that after FMLP, were PT-sensitive (SP = 6.6 +/- 2 pm/mg/min vs SP + PT = 1.1 +/- 0.9 over basal activity; TGF-beta 1 = 4.3 +/- 1.6 vs TGF-beta 1 + PT = 2.3 +/- 0.9). In parallel, treatment of PMN with PT (1 microgram/ml, 30 min) inhibited chemotaxis (under agarose) after FMLP (2175 +/- 176 (SEM) microns vs 726 +/- 267) and SP (411 +/- 99 microns vs 103 +/- 62 microns) and TGF-beta 1 (40 fM, 375 +/- 53 microns vs 83 +/- 47). However, G proteins coupled to receptors for SP and TGF-beta 1, unlike FMLP, did not appear to be linked to phospholipases in that neither increments in diacylglycerol were detected after receptor ligation (FMLP = 152 +/- 22% resting levels; SP = 101 +/- 5%; TGF-beta 1 = 105 +/- 4%) nor was alkylacylglycerol increased by exposure to SP or TGF-beta 1 (SP = 92 +/- 4%; TGF-beta 1 = 101 +/- 8%; FMLP = 226 +/- 40%). Moreover, polymorphonuclear leukocytes failed to generate phosphatidates (PA) of either species after SP (DA-PA = 79 +/- 9% resting at 60 s; EA-PA = 103 +/- 4%) or TGF-beta 1 (DA-PA = 101 +/- 5%; EA-PA = 98 +/- 9%) in contrast to FMLP (DA-PA = 155 +/- 22%; EA-PA = 149 +/- 16%). The data clearly contravene the current dogma that all chemoattractants use inositol trisphosphate and diglycerides as intracellular signals and suggest the presence of a unique subset of PT-sensitive G proteins, not coupled to "classical" phospholipases, transduce chemoattraction.
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PMID:Chemoattraction of neutrophils by substance P and transforming growth factor-beta 1 is inadequately explained by current models of lipid remodeling. 768 33

We are interested in the mechanisms of ozone-induced lung effects after short-term exposure and the relationship with subsequent pulmonary inflammation and disease. Our hypothesis is that ozone, as a powerful oxidant, will diminish the activity of neutral endopeptidase (NEP) in the airways of humans with resulting increased concentrations of neuropeptides such as substance P (SP). We have exposed seven (two women, five men) healthy, nonsmoking individuals (22 to 30 yr of age) to filtered air and ozone (0.25 ppm) for 1 h in an environmental chamber during heavy exercise. Bronchoscopy with airway lavage (AL) and bronchoalveolar lavage (BAL) was performed immediately after ozone exposure. The lavage samples were analyzed by enzyme immunoassay for SP and 8-epi-prostaglandin F2 alpha (8-epi-PGF2 alpha) (a marker for oxidative free radical reaction) and by radioimmunoassay for complement fragments. FEV1 had declined 12.4 +/- 1.9% (mean +/- SEM) as a result of ozone exposure. The AL concentration for SP and 8-epi-PGF2 alpha and BAL concentration of C3a after ozone exposure were significantly higher than after the filtered air exposure (P < 0.05). There was a significant correlation between SP and 8-epi-PGF2 alpha concentrations in the AL fluid (r2 = 0.89 and P < 0.05). There were no changes in C5a in either compartment or any of the mediators in the plasma samples. These results extend previous results from animal studies suggesting that ozone's mechanism of action is through an oxidative reaction resulting in a decreased activity of NEP in the airways with a subsequent increase in the concentration and activity of SP.
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PMID:Ozone-induced increases in substance P and 8-epi-prostaglandin F2 alpha in the airways of human subjects. 769 98


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