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)

1. Opioids have been shown to inhibit substance P (SP) release from primary afferent neurones (PAN). In addition, opioid receptors have been identified on PAN of the vagus nerves. Sodium cromoglycate (SCG) decreases the excitability of C-fibres in the lung of the dog in vivo. We have utilised a multi-superfusion system to investigate the effect of opioids and SCG on the release of SP from the rat trachea in vitro. 2. Pretreatment of newborn rats with capsaicin (50 mg kg-1 s.c. at day 1 and 2 of life) resulted in a 93.2 +/- 6.3% reduction in tracheal substance P-like immunoreactivity (SP-LI) content when determined by radioimmunoassay in the adult. 3. Exposure to isotonically elevated potassium concentrations (37-90 mM), capsaicin (100 nM-10 microM), and bradykinin (BK; 10nm-1 microM) but not des-Arg9-BK (1 microM) stimulated SP-LI release by a calcium-dependent mechanism. 4. SCG (1 microM and 100 microM) did not affect spontaneous, potassium (60 mM)- or BK (1 microM)-stimulated SP-LI release. 5. Morphine (0.1-100 microM) caused dose-related inhibition of potassium (60 mM)-stimulated SP-LI release with the greatest inhibition of 60.4 +/- 13.7% at 100 microM. The effect of morphine was not mimicked by the kappa-opioid receptor agonist, U50,488H (10 microM) or the delta-opioid receptor agonist, Tyr-(D-Pen)-Gly-Phe-(D-Pen) (DPDPE). 6. The effect of morphine was totally abolished by prior and concomitant exposure to naloxone (100 nM) which had no effect on control release values. 7. We conclude that opioid receptors, predominantly of the MM-opioid receptor subtype, inhibit SP-LI release from PAN in the rat trachea and suggest that centrally inactive MM-opioid receptor agonists may have therapeutic potential in the treatment of asthma.
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PMID:Morphine, but not sodium cromoglycate, modulates the release of substance P from capsaicin-sensitive neurones in the rat trachea in vitro. 171 4

1. The role of gamma-aminobutyric acid (GABA) as an inhibitory transmitter in the central nervous system is well documented. Recently, GABAA and GABAB receptors have been identified in the peripheral nervous system, notably on primary afferent neurones (PAN). We have utilised a multi-superfusion system to investigate the effect of selective GABA receptor agonists and antagonists on the release of substance P (SP) from the rat trachea in vitro. 2. GABA (1-100 microM) did not affect spontaneous release of SP-like immunoreactivity (LI) but caused dose-related inhibition of calcium-dependent potassium (60 mM)-stimulated SP-LI release. The greatest inhibition of 77.7 +/- 18.8% was observed at 100 microM. 3. The inhibitory effect of GABA was mimicked by the GABAB receptor agonist, (+/-)-baclofen (1-100 microM), but not the GABAA receptor agonist, 3-amino-1-propane-sulphonic acid (3-APS, 1-100 microM). Baclofen (100 microM) had no effect on SP-LI release stimulated by capsaicin (1 microM). 4. The inhibitory effect of baclofen (30 microM) was significantly reduced by prior and concomitant exposure to the GABAB receptor antagonist, phacolofen (100 microM) but not the GABAA receptor antagonist, bicuculline (10 microM). Neither antagonist, alone, affected spontaneous or potassium-stimulated SP-LI release. 5. We conclude that activation of pre-synaptic GABAB receptors on the peripheral termini of PANs in the rat trachea inhibits SP-LI release and suggest that GABAB receptor agonists may be of value in the therapeutic treatment of asthma.
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PMID:GABAB receptor modulation of the release of substance P from capsaicin-sensitive neurones in the rat trachea in vitro. 171 5

myo-Inositol uptake in prisms of rat parotid glands was investigated by measuring both the accumulation of free myo-[3H] inositol into the cytosol and its incorporation into phospholipids. Total myo-[3H]inositol uptake involved two distinct processes, a prominent one which is saturable and sodium-dependent (Km, 95 microM; Vmax, 8 pmol/mg of protein per min) and a minor one, nonsaturable and sodium-independent. Phloretin and cytochalasin B, two inhibitors of hexose transport, and D-glucose, but only at high concentrations (greater than 10 mM), inhibited myo-[3H]inositol uptake. Dixon plots of the data indicated that D-glucose inhibition was noncompetitive suggesting that myo-inositol and D-glucose are transported by different carriers. Electrogenic cotransport of sodium and myo-inositol, rather than energy derived from mitochondrial oxidative metabolism, seems to be involved in the transport process. Thus, ouabain, monensin or veratridine, all of which increase intracellular sodium concentrations, reduced myo-[3H]inositol uptake, whereas dinitrophenol, potassium cyanide and carbonyl cyanide m-chlorophenyl hydrazone were without effect. Substance P affected only the sodium-dependent uptake process of myo-[3H]inositol, this inhibitory effect requiring extracellular calcium. Similar observations were made with the muscarinic agonist carbachol. From these results, an increase in intracellular sodium concentration linked to the activation of calcium-sensitive cation-permeant channels appears to be responsible for the inhibitory effects of substance P and carbachol on myo-[3H]inositol uptake, these effects being mediated respectively by NK1 and muscarinic receptors coupled to a phospholipase C.
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PMID:Inhibitory effects of substance P and carbachol on the saturable sodium-dependent uptake process of myo-inositol in rat parotid gland. 171 64

The effect of barium on isolated acini was tested. Barium in the 0.1-10 mM concentration range non-competitively inhibited the efflux of 86Rb+ stimulated by carbamylcholine or substance P. This inhibition was independent of the presence of calcium in the extracellular medium. In the same preparation, barium did not affect the efflux of 45Ca2+ but, at a 10 mM concentration, it increased amylase release by 70%. Removal of extracellular calcium decreased basal amylase release and the response to carbamylcholine. Adding back calcium or barium to the incubation medium increased basal and carbamylcholine-stimulated amylase secretion, but calcium was more effective than barium. These results suggest that barium has two opposite effects on calcium-regulated processes in rat parotid gland: (1) it is an inhibitor of calcium-activated potassium channels; (2) it is a partial agonist of calcium-activated amylase secretion.
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PMID:Response of rat parotid acini to barium. 171 13

5-HT3 receptors may be present on primary afferent neurons containing substance P (SP), neurokinin A (NKA) or calcitonin gene-related peptide (CGRP). We investigated the release of SP-, NKA- and CGRP-immunoreactivities (IR) from rat spinal cord slices. Thirty mM potassium chloride caused an increased outflow of all three peptides, i.e. 140-190% of spontaneous release. This release was slightly enhanced in the presence of 3 x 10(-5) M 5-hydroxytryptamine (5-HT). In contrast, a significant inhibition of potassium-evoked, but not of basal NKA-IR and CGRP-IR release was observed when 10(-7) M BRL 43694 or ICS 205-930, two specific 5-HT3 receptor antagonists, were superfused together with 5-HT. In conclusion, 5-HT may facilitate the evoked release of peptides from central terminals of primary sensory neurons via 5-HT3 receptors.
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PMID:5-HT3 receptor antagonists inhibit sensory neuropeptide release from the rat spinal cord. 171 37

Mast cells are involved in allergic reactions where they release numerous vasoactive and other mediators in response to IgE and antigen. They are also activated by neuropeptides and are found in close contact with neurons. Mast cell heterogeneity has now been documented for mucosal mast cells and connective tissue mast cells. Rat brain mast cells were studied in a perfusion system and were shown to release serotonin in response to the mast cell secretagogue compound 48/80 (C48/80). High-potassium neuronal depolarization also released serotonin, but this was calcium dependent, not associated with beta-hexosaminidase, and was unaffected by prior treatment with C48/80. Neuronal depolarization, however, was associated with somatostatin secretion and substantially reduced subsequent C48/80 stimulation, an effect abolished by neonatal treatment of the animals with capsaicin. Perfusion with somatostatin and substance P also induced brain mast cell serotonin release. C48/80 stimulation of combined thalamic and hypothalamic slices after neuronal depolarization substantially reduced the C48/80 effect, suggesting the possible presence of endogenous inhibitors released from the hypothalamus. Finally, the alpha 2-receptor agonist clonidine had a slight stimulatory effect. These results indicate that brain mast cell serotonin release may be regulated by endogenous neurotransmitters and/or neuromodulators.
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PMID:Endogenous regulation of rat brain mast cell serotonin release. 172 Apr 23

An increase in inositol 1, 4, 5-trisphosphate (IP3) formation in rat mast cells precedes an elevation in intracellular Ca2+ levels, which triggers the process(es) leading to histamine release. By means of a transmission electron microscope, it was revealed that when permeabilized mast cells were exposed to potassium antimonate, antimonate precipitates in the endoplasmic reticulum (ER) in the form of calcium antimonate, indicating that the ER is the intracellular Ca store in rat mast cells. IP3 at concentrations higher than 0.5 microM preferentially releases Ca2+ from the isolated ER of mast cells. GTP was also effective in releasing Ca2+ from the ER. IP3-induced Ca2+ release was inhibited by pretreatments with cAMP and antiallergic drugs. An increase in the intracellular Ca2+ concentration may lead to an activation of calmodulin, C kinase and cytoskeletal elements in sequence. Furthermore, microtubules may play an important role in the process(es) leading to Ca2+ release from the intracellular Ca store and subsequent histamine release, without affecting IP3 formation. In contrast, microfilaments seem to participate not only in the extrusion but also in the reincorporation of the mast cell granules, having no influence on intracellular Ca2+ release. Substance P (SP) is one of the most effective neuropeptides for releasing histamine from mast cells. Structure-activity relationship studies indicate that basicity at the N-terminal and hydrophobicity at the C-terminal are requisite for its histamine releasing activity. SP effectively released Ca2+ from the intracellular Ca store. The site of action of SP on the mast cell surface seems to be the same as that of compound 48/80. Eosinophil major basic protein (MBP) and histone are also effective for releasing histamine. The cDNA sequences of two subclasses of guinea pig MBP have been determined. These proteins may be released at the site of inflammation from the cells activated by the chemical mediators released from mast cells, and consequently, mast cell activation was reinforced. Such cell-to-cell interaction may be the reason for the augmentation of inflammation.
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PMID:[Recent advances in the research on histamine release]. 172 Jul 58

In the present study the effects of activation of capsaicin-sensitive C-fibre afferents by resiniferatoxin and capsaicin as well as the effects of the co-stored peptides calcitonin gene-related peptide substance P and neurokinin A on porcine coronary vascular tone in vitro was investigated. Resiniferatoxin, capsaicin, calcitonin gene-related peptide and neurokinin A all evoked a sustained, concentration-dependent vasodilatation of potassium (60 mM)-precontracted arteries. Substance P also caused vasodilatation of the precontracted arteries but this effect was transient and tachyphylaxis developed rapidly upon repeated administration. Incubation with the calcitonin gene-related peptide fragment (8-37) did not influence the vascular tone per se but markedly attenuated the dilatory effect of calcitonin gene-related peptide and totally abolished the vasodilatation induced by resiniferatoxin and capsaicin while leaving the effect of neurokinin A and substance P unaltered. Incubation with methylene blue, an inhibitor of endothelium-derived relaxing factor mechanisms, which completely blocked the substance P-evoked vasodilatation, as well as substance P-tachyphylaxis, did not influence the vasodilator response to resiniferatoxin, capsaicin or calcitonin gene-related peptide. The neurokinin A-evoked vasodilatation was most likely mediated through activation of neurokinin 1-receptors since it remained unchanged in the presence of the neurokinin 2-receptor antagonist dactinomycin and (Nle10)-neurokinin A (4-10), which selectively activates neurokinin 2-receptors, had only a minor dilatory effect on the precontracted arteries.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Resiniferatoxin-, capsaicin- and CGRP-evoked porcine coronary vasodilatation is independent of EDRF mechanisms but antagonized by CGRP(8-37). 172 40

The effect of acrylamide intoxication on the innervation and local control of the rabbit central ear artery was investigated. There was no difference in the noradrenaline, neuropeptide Y and calcitonin gene-related peptide tissue content between control and experimental animals. There was, however, a slight reduction in catecholamine histofluorescence. Although the contractile efficiency of the rabbit central ear artery as measured by responses to potassium chloride was unchanged, nerve-mediated contractile responses were significantly attenuated in acrylamide-treated animals. Contractile responses induced by exogenous alpha,beta-methylene ATP were markedly increased after acrylamide treatment, in contrast to contractions induced by exogenous noradrenaline which were attenuated at maximal concentrations. Modulatory effects of nerve-mediated contractile responses by neuropeptide Y were unaffected by acrylamide intoxication. It therefore appears that acrylamide intoxication damages sympathetic cotransmission, perhaps with preferential action on the purinergic component. Endothelium-dependent relaxant responses to acetylcholine and substance P were attenuated in acrylamide-treated animals, whereas relaxant responses mediated by calcitonin gene-related peptide (endothelium independent) were unaffected. The question of whether the damage to the endothelial cell action is a primary effect, or a secondary consequence of sympathetic nerve damage, is discussed.
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PMID:Changes in sympathetic and endothelium-mediated responses in the rabbit central ear artery after acrylamide treatment. 175 64

Bombesin-like immunoreactivity is present in nerve fibers projecting to the cardiovascular system, including the coronary arteries, and to the gastrointestinal canal, and in endocrine cells of the gut of skates belonging to the family Rajidae. Synthetic bombesin contracted isolated coronary rings from the longnose skate, Raja rhina, in a cumulative fashion. The contractile response was 84% of that of 60 mM potassium chloride. The pD2-value for bombesin was 8.83 (S.E.M. = 0.33; n = 15). Phentolamine, atropine and two substance P-antagonists increased the sensitivity to bombesin, while atenolol, sotalol, nifedipine, tetrodotoxin and two bombesin antagonists were devoid of significant effects. We conclude from this study that a bombesin-like peptide is present in nerves innervating the cardiovascular system and the gastrointestinal canal of skates of the family Rajidae, and that bombesin contracts coronary vessels in vitro via a direct mechanism and/or via mechanisms involving alpha-adrenergic and muscarinergic receptors.
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PMID:Bombesin-like immunoreactivity in skates and the in vitro effect of bombesin on coronary vessels from the longnose skate, Raja rhina. 175 76


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