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

The endothelium-dependent (acetylcholine, bradykinin, substance P) and the endothelium-independent (gliceryl trinirate, 3-morpholinsydnominine, sodium nitroprusside) vasodilators were studied in the Langendorff-perfused heart of the guinea pig. The involvement of prostanoids and EDRF in the endothelium-dependent responses were assessed by using indomethacin, an inhibitor of cyclooxygenase, and NG-nitro-L-Arginine, an inhibitor of NO synthase. The endothelium-independent agents were used as reference compounds. Both indomethacin and NG-nitro-L-Arginine elevated significantly baseline coronary perfusion pressure, indicating that prostanoids (most likely PGI2 and PGE2) and EDRF modulate the resting tone of the guinea pig coronary circulation. NG-nitro-L-Arginine, but not indomethacin, considerably reduced receptor-stimulated responses. It is concluded that acetylcholine, bradykinin or substance P-induced vasodilation is mediated by EDRF. In contrast, prostanoids do not contribute to endothelium-dependent responses. In addition, short-term tachyphylaxis to bolus injection of gliceryl trinitrate but not of sodium nitroprusside was demonstrated, suggesting that this preparation may be of value for studying nitrate tolerance.
 ...
PMID:The endothelium-dependent and the endothelium-independent vasodilators in the isolated, perfused guinea pig heart. 129 66

In helical strips cut from the small mesenteric artery of guinea-pig (GPSMA) (0.3-0.6 mm o.d.) relaxations induced by substance P were more susceptible to damage of the endothelium by rubbing than were relaxations evoked by carbachol. Relaxations induced by 2-nicotin-amidoethyl nitrate (SG75) were unaffected by this procedure. Relaxations evoked by the calcium ionophore A23187 persisted when those to substance P had been abolished by rubbing the endothelium in GPSMA, rabbit mesenteric and rabbit ear arteries. In guinea-pig pulmonary artery and aorta relaxations to A23187 were lost after this treatment. Carbachol and SG75 were more effective in inhibiting phasic than tonic tension induced by noradrenaline in GPSMA, but substance P was more effective against tonic tension. In the GPSMA, carbachol and substance P inhibited tension produced by noradrenaline to similar extents. However, carbachol was less, and substance P much less effective in inhibiting tension evoked by high-potassium solution than by noradrenaline. Susceptibility of relaxations to blockade by haemoglobin in GPSMA was: substance P greater than carbachol greater than ATP greater than SG75. The membrane potential of smooth muscle cells in the media of the GPSMA was recorded by microelectrode. Carbachol, but not substance P, hyperpolarized the cells both in the presence and absence of noradrenaline at concentrations which relaxed the muscle. These results suggest a heterogeneity in the mechanisms of endothelial-dependent relaxations induced by various vascular relaxants.
 ...
PMID:Endothelial-dependent relaxant actions of carbachol and substance P in arterial smooth muscle. 242 70

The ionic basis for the rapid reduction in potential difference (dip) produced on luminal addition of substance P and related peptides was analysed by altering the electromotive force and chemical gradients across the isolated, canine tracheal epithelium. The dip could be exaggerated, minimised or reversed by increasing, decreasing or reversing the basal potential difference, and the intercept of the line relating the two was close to zero when the Cl- compositions of the two bathing solutions were identical. Luminal Cl- replacement by a non-permeant anion (isethionate) attenuated the dip which was, however, exaggerated by a permeant anion (nitrate). Replacement of serosal Na+ or luminal HCO3- had no significant effect on the magnitude of the dip. The tachykinins exhibited cross-tachyphylaxis with each other, indicating a common receptor. Bradykinin, a structurally unrelated peptide, also produced dips upon luminal addition, but showed no cross-tachyphylaxis with the tachykinins. Again, a linear relation between basal potential difference and the dip elicited by bradykinin was observed. Based on current awareness of the bioelectric properties of the canine tracheal epithelium, we suggest that these peptides modulate paracellular anion permeabilities.
 ...
PMID:Peptides increase anion conductance of canine trachea: an effect on tight junctions. 243 14

Modifications of the single-section Golgi-impregnation procedure of Gabbott and Somogyi are described. The modifications allow easier and more rapid preparation of the sections for Golgi-impregnation and easier handling of large numbers of serial sections. The technique consists of placing a section that has been treated with osmium tetroxide and potassium dichromate on a microscope slide and "sandwiching" it with a second microscope slide. The two slides are held together at one end by tape and the assembly is dipped into a solution of silver nitrate. Golgi-impregnation of neurons occurs within a few hours and is generally complete within 12 h. The technique has been applied to sections through the caudate nucleus of the cat and ferret in order to define the morphological characteristics of striatal substance P- and methionine enkephalin-immunoreactive neurons. Sections were first incubated to reveal the immunoreactive structures and then subjected to the Golgi method. Golgi-impregnated neurons that were immunoreactive for either substance P or methionine enkephalin had medium-size perikarya from which several dendrites emerged. The dendrites branched close to the perikaryon; secondary and higher order dendrites were densely laden with spines, as many as 15 spines per 10 microns of dendrite. It is concluded that both striatal substance P-containing and methionine enkephalin-containing neurons are of the medium-size densely spiny type. Medium-size densely spiny neurons may be homogeneous with respect to their somatodendritic morphology but heterogeneous with respect to their chemical characteristics and axonal morphology.
 ...
PMID:Characterization of substance P- and [Met]enkephalin-immunoreactive neurons in the caudate nucleus of cat and ferret by a single section Golgi procedure. 243 93

Human epicardial coronary arteries were obtained from the hearts of 15 patients who received cardiac transplantation for cardiomyopathy. Transverse strips of these arteries were mounted in organ baths for isometric tension recording. The arteries were constricted with prostaglandin F2 alpha and then exposed to the endothelium-dependent relaxants substance P (1 nM), bradykinin (1 nM-1 microM), and the Ca2+ ionophore A23187 (1 nM-1 microM). The effects of the endothelium-independent relaxants glyceryl trinitrate (1 nM-10 microM) and SIN-1, the active metabolite of molsidomine (1 nM-10 microM), were also tested. In control strips of human coronary arteries, all vasodilators caused concentration-dependent relaxations. Pretreatment of human coronary arteries with glyceryl trinitrate (0.5 mM for 60 min) shifted the concentration-response curve to glyceryl trinitrate to the right by a factor of approximately 800 (increase in EC50 from 10 nM to 8 microM). In contrast, endothelium-dependent relaxations to substance P, bradykinin, and A23187 and relaxations to SIN-1 were not changed significantly. Previous exposure of human coronary arteries to SIN-1 (0.5 mM for 60 min) did not modify relaxations to any of the agents tested. Our results show that (a) the responsiveness to SIN-1 is not modified in nitrate-tolerant strips of human coronary arteries, (b) prolonged exposure of human coronary arteries to SIN-1 does not cause tolerance, and (c) endothelium-dependent relaxations are not influenced by exposure of human coronary arteries to either glyceryl trinitrate or SIN-1.
 ...
PMID:Endothelium-dependent vasodilatation in human epicardial coronary arteries: effect of prolonged exposure to glyceryl trinitrate or SIN-1. 248 99

The influence of mineral NPK fertilizers and organic fertilizers such as manure compost, woodchip compost and blood meal on the yields and the nutritive value of leeks and turnips were compared. Fertilizers were applied on the two crops grown successively in 200-1 containers. Mineral fertilizers, manure compost and blood meal provided equivalent vegetable yields. Contents in dry matter, ascorbic acid and minerals of leeks and turnips were not strongly affected by the different fertilization regimes. The nitrate content of both crops was significantly lower under the application of manure compost and woodchip compost, while mineral fertilizers and blood meal induced similar, higher nitrate levels. The present work thus provides new data showing the usefulness of composts in growing vegetables with low nitrate contents.
 ...
PMID:Yield and content in nitrates, minerals and ascorbic acid of leeks and turnips grown under mineral or organic nitrogen fertilizations. 285 3

Some factors influencing the oxidative activity of upper horizons of spruce forest soils (a mixture of fermentative and humus layers) toward intermediates of the oxidative part of the sulphur cycle were investigated. Preincubation of the soil with added cysteine, sulphide, elemental sulphur or thiosulphate was found to stimulate enzyme systems oxidating any of these compounds. Sulphite and sulphate were ineffective in this respect. The oxidation of elemental sulphur was stimulated by CaCO3, technical urea and high doses of superphosphate and potassium sulphate. It was inhibited by KH2PO4, pure urea, 40 % potassium salt, ammonium nitrate with calcium carbonate and the fertilizer NPK I. It proceeded at the highest rate at approximately 60 % capillary capacity (61 % of mass water content). Oxidation of thiosulphate was stimulated by KH2PO4, pure urea, superphosphate, potassium sulphate and only slightly by the fertilizer NPK I. It was inhibited by CaCO3, 40 % potassium salt and only slightly by ammonium nitrate with calcium carbonate. Potassium chloride, glucose and technical urea were without effect. The oxidation proceeded at the highest rate at 35 % maximal capillary capacity (48 % mass water content).
 ...
PMID:Some factors influencing production of sulphate by oxidation of elemental sulphur and thiosulphate in upper horizons of spruce forest soils. 626 35

beta 2-Adrenergic receptor agonists inhibit the increase in vascular permeability produced by a variety of inflammatory mediators. The anti-edema effect of beta 2-agonists is assumed to result from a direct action on endothelial cells, but such a mechanism has not been demonstrated in vivo. The aim of this study was to determine whether beta 2-agonists exert their anti-edema effect by inhibiting the formation of endothelial gaps at sites of plasma leakage. Vascular permeability in the rat trachea was increased by electrical stimulation of the vagus nerve or by intravenous injection of substance P (5 micrograms/kg iv). Plasma leakage was quantified by using Monastral blue and Evans blue as tracers. Endothelial gaps were made visible for light microscopy by staining the borders of endothelial cells with silver nitrate. The experiments showed that the selective beta 2-agonist formoterol, which is known to have anti-edema effects, reduced the plasma leakage produced by either stimulus. The effect was dose dependent, with a formoterol dose of 10 micrograms/kg iv producing maximal reduction of Monastral blue leakage (64 +/- 14%). The amounts of extravasation of Monastral blue and Evans blue were closely correlated (r2 = 0.76, P < 0.01). After the injection of substance P, there were 15.3 +/- 1.0 gaps/endothelial cells in postcapillary venules of vehicle-pretreated rats, but only 5.0 +/- 0.2 gaps/cell in formoterol-pretreated (10 micrograms/kg iv) rats.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:The beta 2-adrenergic receptor agonist formoterol reduces microvascular leakage by inhibiting endothelial gap formation. 751 64

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.
 ...
PMID:Nitrovasodilator-induced relaxation and tolerance development in porcine vena cordis magna: dependence on intact endothelium. 752 Dec 58

Hypertensive patients have impaired endothelium-dependent coronary vasodilation evoked with acetylcholine. The aim of this study was to examine whether the impaired endothelium-dependent dilation of coronary arteries is related to a specific abnormality of the muscarinic receptor that mediates the effects of acetylcholine. Responses of the large epicardial and resistance coronary arteries were assessed in seven hypertensive patients (mean arterial pressure, 106 +/- 14 mm Hg) and seven control subjects (83 +/- 6 mm Hg, P < .01) during cardiac catheterization. To assess coronary endothelial function, we infused acetylcholine and substance P (endothelium-dependent agents that act on different receptors) and papaverine and nitrate (direct vascular smooth muscle dilators) into the left anterior descending coronary artery and determined coronary artery diameter by arteriography and coronary blood flow with an intracoronary Doppler catheter technique. In control subjects, 3 micrograms/min acetylcholine increased (P < .05) and 30 micrograms/min acetylcholine decreased (P < .05) arterial diameter, and in hypertensive patients, 1, 3, 10, and 30 micrograms/min acetylcholine decreased arterial diameter in a dose-dependent manner. Substance P at 3, 10, and 30 ng/min caused comparable increases in diameter in both groups. Increases in coronary blood flow with both acetylcholine and substance P were significantly (P < .01) blunted in hypertensive patients compared with control subjects. No significant differences were noted between the groups in the responses of large epicardial coronary artery diameter and coronary blood flow to papaverine and nitrate.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Impaired endothelium-dependent vasodilation of large epicardial and resistance coronary arteries in patients with essential hypertension. Different responses to acetylcholine and substance P. 753 Nov 75


1 2 3 4 5 6 7 Next >>