首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
Opiate agonists, morphine, levorphanol and beta-endorphin increased calcium accumulation in rat peritoneal mast cells. This effect was dose dependent and beta-endorphin was 10 times more potent than morphine. The stimulation was stereospecific and inhibited by naloxone. The site of the opiate action appears to be on the outer surface of the plasma membrane since lysis of the mast cell did not alter the response to morphine. Tolerance to the opiate effect was not seen after chronic morphine administration. Morphine did not stimulate histamine release even at relatively high doses in vivo or high concentrations in vitro. It is reasoned that the enhancing effects on external calcium accumulation may reduce the critical cytosol calcium level for effecting histamine release.  相似文献   

2.
Compound 48/80-induced histamine release from isolated rat peritoneal mast cells was inhibited in a dose-dependent manner by papaverine (ic50 approx 20 μM). This effect of papaverine was not influenced by PGE1 (14–140 μM), even though PGE1 markedly increased must cell cAMP levels. Papaverine (0.5 mM) completely inhibited histamine release without causing any change in cAMP levels. Theophylline (0.1 and 0.5 mM) potentiated histamine release induced by submaximal concentrations of compound 48/80, while cAMP levels were increased. IBM X was as potent as papaverine in causing inhibition of mast cell phosphodiesterase. IBM X (0.14–0.7 mM) had no effect on histamine release but caused a 6–20 fold increase in mast cell cyclic AMP. Papaverine inhibition of histamine release was gradual at the onset and was parallelled by a depletion of mast cell ATP content. The inhibition of 48/80-induced histamine release and depletion of mast cell ATP levels was reversed by glucose. It is concluded that papaverine induced inhibition of 48/80-induced histamine release is independent of cAMP, is unrelated to phosphodiesterase inhibition but is dependent upon inhibition of energy production.  相似文献   

3.
The inhibition of energy metabolism of mast cells causes an inhibition of histamine secretion. As the secretion is generally initiated by the influx of calcium into the cell, we have made correlative studies of the effect of blocking the energy metabolism on calcium uptake and histamine secretion. When the influx of calcium is increased by exposing the cells to low concentrations of saponin or ionophore A23187, histamine release occurs, having the character of a secretory response. Brief incubation of the cells with antimycin A, 10(-9) M-10(-7) M, prior to exposure to saponin or the calcium ionophore gave similar dose-response curves for the inhibitory effect of antimycin A on calcium uptake and histamine release. The inhibition of calcium uptake in untreated mast cells by antimycin A, 10(-9) M-10(-7) M, showed good correlation to the inhibition of anaphylactic histamine release and the release induced by compound 48/80. The antigen-induced histamine release is dependent on extracellular calcium and an inhibition of its uptake by antimycin A could by itself inhibit the release. Compound 48/80 on the other hand induces histamine release both in the presence and absence of calcium, and both are similarly inhibited by 10(-9) M-10(-7) M antimycin A. This indicates that antimycin A has other sites of action apart from the inhibition of the influx of extracellular calcium. The inhibitory effect of antimycin A on compound 48/80-induced histamine secretion in the absence of extracellular calcium may be due to an inhibition of energy requiring steps in the final phase of the secretory process.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

4.
We studied the in vitro effects of FPL-52694 [5-(2-hydroxypropoxyl)-8-propyl-4-oxo-4H-benzopyran-2-carboxylic acid Na] on histamine release from rat peritoneal mast cells. These cells exposed to ascaris antigen, compound 48/80 or the ionophore A 23187 concentration-dependently released histamine. About a 30-40% histamine release was obtained by 1 X 10(-4) g/ml of antigen, 1 X 10(-7) g/ml of compound 48/80 and A 23187. FPL-52694 (10(-9)-10(-4) g/ml) concentration-dependently inhibited the histamine release from mast cells in response to antigen (1 X 10(-4) g/ml) and compound 48/80 (1 X 10(-7) g/ml), but only slightly inhibited the histamine release induced by A 23187 (1 X 10(-7) g/ml). Similar results were obtained with disodium cromoglycate (DSCG), in the same dose ranges. However, the inhibitory activity of FPL-52694 on histamine release by antigen and compound 48/80 was approximately 10 times more potent than that of DSCG at certain concentrations. Tachyphylaxis was observed when these two agents were preincubated with mast cells for 10 min. These results show FPL-52694 to be a novel mast cell stabilizer.  相似文献   

5.
We have previously reported an inhibition of histamine release by TMB-8 both in the presence and absence of calcium and with glucose in the medium. In the present investigation we have studied the effect of TMB-8 on calcium transport. The observations show that TMB-8 inhibits calcium uptake and enhances calcium efflux in mast cells. As antigen-induced histamine release from sensitized mast cells is primarily dependent on extracellular calcium, the inhibition of anaphylactic histamine release by TMB-8 is probably mainly due to an inhibition of calcium influx into the mast cells. We have shown an increased calcium efflux during histamine release from mast cells induced by compound 48/80 in the absence of calcium in the medium, suggesting the release of intracellular calcium stores. The increased calcium efflux was not inhibited by TMB-8. On the contrary, the enhanced calcium efflux caused by compound 48/80, was added to that by TMB-8. TMB-8 thus had no effect on the calcium release from intracellular stores by compound 48/80 but the enhanced calcium efflux by TMB-8 would tend to inhibit histamine release.  相似文献   

6.
Summary using pure populations of rat mast cells, the relation of the ATP content of the cells to histamine release induced by compound 48/80 has been studied. Variable ATP levels in the mast cells have been produced by incubation with appropriate concentrations of oligomycin.The dose-response curves of oligomycin for the inhibition of histamine release and for the reduction in the ATP content of the mast cells are similar. The concentration required for 50% inhibition of histamine release is, however, higher than that for 50% reduction of the ATP level.Comparative study of the reduction of the ATP content and the inhibition of histamine release in samples of the same suspension of mast cells shows a linear relation between 10 to 90% inhibition of histamine release and 40 to 95% inhibition of ATP synthesis.The observations support the hypothesis that ATP is involved in the process of histamine release from mast cells induced by compound 48/80.  相似文献   

7.
Histamine release from rat peritoneal mast cells induced by anti-IgE was potentiated by the retinoids: retinoic acid 2-10 microM and retinal 1-5 microM. Retinal also produced a concentration-dependent increase in anti-IgE-stimulated 45Ca uptake by these mast cells. A similar potentiating action of both retinoids was observed on histamine release induced by 12-O-tetradecanoylphorbol-13-acetate (TPA). For both anti-IgE- and TPA-induced histamine release, the potentiating effect of the two retinoids was only observed in the presence of extracellular calcium. In contrast, histamine release induced by compound 48/80 was inhibited by retinal 1-5 microM and by retinoic acid 10-50 microM and the inhibition was the same in the presence as in the absence of extracellular calcium 1 mM. Histamine release induced by calcium and the calcium ionophore A 23187 was inhibited by retinoid acid 2-10 microM and by retinal 10 microM. Inhibitions of compounds 48/80-induced histamine release by cromoglycate and by retinal were additive. It is concluded that while the actions of retinoids on rat peritoneal mast cells are consistent with the inhibition of protein kinase C, another action of these compounds, unrelated to this enzyme, may explain the data.  相似文献   

8.
The actions of the antiallergic agents, disodium chromoglycate (DSCG), tranilast and ketotifen, and of a calcium channel antagonist, nicardipine, and cross-reactivity among the agents were examined by observing the inhibition of 45Ca uptake and histamine release in rat mast cells stimulated by antigen and compound 48/80 (comp. 48/80). 1) All agents inhibited 45Ca uptake and histamine release in mast cells stimulated by antigen. The inhibition of 45Ca uptake by the antiallergic agents paralleled the inhibition of histamine release, while nicardipine inhibition of 45Ca uptake was stronger than its inhibition of histamine release. 2) The action of DSCG on 45Ca uptake and histamine release was significantly decreased in cells stimulated with antigen and phosphatidylserine (PS), while tranilast inhibition of histamine release was not affected by the addition of PS despite a significant decrease in the inhibition of 45Ca uptake. 3) The inhibitory effect of DSCG and tranilast was significantly lower in mast cells stimulated by comp. 48/80 than in the cells stimulated by antigen. 4) Tachyphylaxis was observed in cells re-exposed to DSCG and tranilast following previous exposure to the agents. 5) Cross-reactivity was found between DSCG and tranilast.  相似文献   

9.
In these experiments the effects of pharmacological concentrations of auranofin, a new absorbable gold compound, were assessed on the release of histamine and peptide leukotriene C4 (LTC4) from human basophils and lung mast cells. Auranofin, at pharmacological concentrations, inhibited in vitro histamine and LTC4 release from human basophils induced by anti-IgE. Inhibition began at about 3 X 10(-7) M and was maximum at 10(-5) M. We also evaluated the effect of auranofin on the release of histamine and LTC4 induced by anti-IgE from mast cells purified from human lung. Auranofin (3 X 10(-7) to 10(-5) M) dose-dependently inhibited the release of histamine and LTC4 from human lung mast cells. Thus pharmacological concentrations of auranofin cause dose-related inhibition of histamine release and de novo synthesis of LTC4 by human basophils and lung mast cells.  相似文献   

10.
The effect of 11 flavonoids and 4 biflavonoids on the release of histamine from peritoneal rat mast cells induced by compound 48/80 and calcium ionophore A23187 was studied. Dihydroflavonoids (flavanones) and (+)-catechin did not modify histamine release induced by both secretagogues. Flavone, apigenin and cromoglycate inhibited the secretion elicited by compound 48/80 but did not modify the A23187-induced secretion. The effect of kaempferol on the compound 48/80-induced histamine release was biphasic. Low doses (10 (-6) to 10 (-5)M) of the compound potentiated secretion whereas higher doses inhibited histamine secretion. Some of the drugs tested revealed a higher potency as referred to quercetin. Luteolin, a tetrahydroxyflavone and amentoflavone, a biapigenin, exhibited the highest inhibitory effects of mast cell histamine secretion.  相似文献   

11.
Oosponol (4-hydroxymethylketone-8-hydroxyisocoumarin) is a metabolic product isolated from Oospora astringens which originated from house dust in a room of an asthmatic patient. The compound and the structurally related isocoumarins were studied to determine the inhibition of histamine release induced by compound 48/80 from isolated rat peritoneal mast cells. The released histamine was assayed by fluorometry. The compounds tested were not observed to release histamine. Some of 4-acyl-isocoumarins inhibited the histamine release at doses less than 10 micrometers, whereas the 3-acyl- and the 4-alkyl-compounds were not effective at doses over 100 microns. The pretreatment of mast cell with the compound for 15 min before the application of compound 48/80 was more effective than the simultaneous administration. The mode of inhibitory action of KIT-302, 4-(4'-carboxy-benzoyl)-isocoumarin, was non-competitive antagonism to compound 48/80 on the mast cells.  相似文献   

12.
Selective release of histamine from rat peritoneal mast cells in vitro was induced by compound 48/80 (1 microgram/ml). Most of the release (75-80%) occurred in a calcium(Ca)-free medium but optimum release was obtained in the presence of 0.9 mM Ca. The release in Ca-free medium still occurred after 180 min incubation. However, prolonged incubation (180 min) in a medium containing chelating agents (EDTA or EGTA) resulted in complete inhibition of histamine release, loss of fluorescence seen with chlortetracycline (CTC) and loss of previously loaded 45Ca from the mast cells. Addition of Ca to these cells resulted in rapid restoration of fluorescence with chlortetracycline. There was also a rapid uptake of 45Ca. Partial depletion of cellular Ca (60 min incubation with EDTA) reduced the rate as well as the amount of histamine release by compound 48/80. These data provide direct evidence for the depletion of cellular Ca which is utilized by compound 48/80 to induce histamine release.  相似文献   

13.
The response of the isolated vas deferens of the mouse to electrical stimulation is inhibited by morphine and levorphanol via an opiate receptor, the inhibition decreasing with increasing stimulation frequency (0.2-16 Hz). Tolerance to the locomotor stimulant effect of morphine was induced over 48 h using a slow release preparation. Vasa from mice similarly treated with the slow release preparation showed a shift to the right of the morphine and levorphanol twitch inhibition curves. The reduction in the fractional release of [3H]noradrenaline by morphine and levorphanol was less in vasa from morphine-pretreated mice. Altering the Krebs solution by reducing the Ca2+ or Na+ or adding Mg2+ increased the effect of opiate agonists in vasa from naive and morphine-tolerant mice. Therefore, tolerance to morphine has not changed the ability of these ions to modulate opiate responses.  相似文献   

14.
Abstract: Histamine release and lactate content were concomitantly determined in samples of isolated rat mast cells. Histamine release induced by exogenous ATP or compound 48/80 was inhibited by antimycin A (0.2 μM). Glucose (0.60 mM) restored the release induced by compound 48/80 but not that induced by ATP. ATP but not compound 48/80 inhibited the accumulation of lactate in suspensions of mast cells containing glucose (0.60 mM). ATP induced inhibition of lactate accumulation and release of histamine within the same concentration range. However, the time courses for the two processes were different. Antimycin A (0.2 μM) enhanced the accumulation of lactate, an effect which was counteracted by ATP. 0.05 mM ATP or more reduced the lactate accumulation to the same values as those found in the absence of antimycin A. The inhibitory action of ATP on glycolysis may explain the observed inability of glycolytic substrates to restore the ATP-induced histamine release blocked by inhibitors of oxidative metabolism.  相似文献   

15.
Intravenous administration of morphine sulfate often produces urticarial and hypotensive reactions associated with elevations in plasma histamine. The source of this histamine and mechanisms controlling its release are poorly understood. Previous studies of morphine-induced histamine release compared human leukocytes to rat peritoneal mast cells. The effects of morphine on human cutaneous mast cells has not been examined. We studied in vitro histamine release from human basophils and human skin preparations containing cutaneous mast cells to evaluate their relative contribution to the pharmacologic effects of morphine. Human skin mast cell preparations showed dose-dependent histamine release over a morphine concentration range of 1.5 X 10(-5) to 4.5 X 10(-3) M, with peak release occurring at 5 X 10(-4) M, with peak release occurring at 5 X 10(-4) M. Clinically, morphine sulfate is usually injected as a 1.5 X 10(-2) M solution. Histamine release was calcium dependent and equivalent to that obtained with 3 and 10 mM strontium. Morphologic examination revealed degranulation and exocytosis occurring in morphine-stimulated tissue but not in specimens exposed to buffer alone. Lactate dehydrogenase levels did not increase following morphine incubation, thus supporting a noncytolytic mechanism of histamine release. Basophils, in contrast, showed no significant histamine release from exposure to morphine up to 10(-2) M. Concanavalin A, as a positive control in these same preparations, produced a mean histamine release of 21.0%.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

16.
1. Human skin mast cells, unlike other human mast cells so far studied, released histamine in a concentration-related manner in response to substance P, vasoactive intestinal peptide (VIP) and somatostatin (1 microM to 30 microM). In contrast, eledoisin, physalaemin, neurokinin A, neurokinin B, calcitonin gene-related peptide (CGRP), neurotensin, bradykinin and Lys-bradykinin induced negligible histamine release. 2. The low histamine releasing activity of physalaemin, eledoisin, neurokinin A and neurokinin B relative to substance P suggests that the human skin mast cell activation site is distinct from the tachykinin NK-1, NK-2 or NK-3 receptors described in smooth muscle. 3. The relative potencies of substance P and its fragments SP2-11, SP3-11, SP4-11 and SP1-4 in releasing histamine from human skin mast cells suggests that both the basic N-terminal amino acids and the lipophilic C-terminal portion of substance P are essential for activity. 4. Peptide-induced histamine release, like that induced by compound 48/80, morphine and poly-L-lysine, is rapid, reaching completion in 10-20 s, is largely independent of extracellular calcium but requires intact glycolysis and oxidative phosphorylation. 5. The substance P analogue, [D-Pro4,D-Trp7,9,10] SP4-11 (SPA), not only reduced substance P-induced histamine release in a concentration-related manner but also inhibited that induced by VIP, somatostatin, compound 48/80, poly-L-lysine and morphine but not anti-IgE. 6. The similar characteristics of histamine release induced by substance P, VIP, somatostatin, compound 48/80, poly-L-lysine and morphine suggest that they share a common pathway of activation-secretion coupling distinct from that of IgE-dependent activation. Furthermore, the ability of human skin mast cells to respond to basic non-immunological stimuli including neuropeptides may reflect a specialised function for these cells.  相似文献   

17.
The relation between calcium influx and histamine release from rat mast cells was investigated. When purified mast cells pretreated with a calcium antagonist (MnCl2 or methoxyverapamil (D-600)) were exposed to concanavalin A or compound 48/80 in Tyrode solution (pH 7.4) at 37°C, the calcium antagonists inhibited the extracellular calcium-dependent component of concanavalin A-induced histamine release. MnCl2 also inhibited the extracellular calcium-dependent component of compound 48/80-induced histamine release, whereas D-600 did not inhibit the release. D-600 inhibited the 45Ca uptake induced by concanavalin A, but did not inhibit the 45Ca uptake induced by compound 48/80. It was found that the inhibitory action of calcium antagonists depended on the uptake of extracellular calcium. These observations suggest that concanavalin A and compound 48/80 stimulate different mechanisms of calcium influx. Studies on inactivation of the mechanisms of calcium influx showed that calcium influx into cells activated by concavalin A stopped when concanavalin A was washed out, whereas the influxactivated by compound 48/80 was still operative after compound 48/80 had been washed out.  相似文献   

18.
Histamine-retaining granules were isolated from rat mast cells after sonication in either sucrose of Ficoll-Hypaque media. The preparations obtained were compared in regard to recovery and spontaneous loss of histamine. The effect of agents known to release histamine from intact rat mast cells (antigen, compound 48/80, decylamine, the ionophores A23187 and X537A as well as ATP) was studied on the granules. Antigen and compound 48/80 did not release histamine. Decylamine and X537A induced a pronounced release independent of the presence of divalent cations. ATP caused a small, but significant release, which showed an absolute requirement for magnesium. A23187 released histamine only in the presence of either calcium or magnesium, and this release was unaffected by certain agents known to inhibit histamine release from intact rat mast cells. The results seem to exclude the possibility that agents known to induce release of histamine from intact rat mast cells by a calcium-and energy-dependent process would exert this action through a direct effect on intracellularly localized granules.  相似文献   

19.
Adrenergic agonists inhibit the release of histamine from rat pleural and peritoneal mast cells stimulated with compound 48/80 to a degree dependent on their beta-activity. Isoprenaline takes part in a stereoselective inhibitory action in the range 10(-7)-10(-4) M. Adrenaline induces a similar response pattern, with inhibition at higher concentrations. The response profile, but not the maximum values of inhibition, is clearly dependent on the concentration of the histamine releaser. Noradrenaline by itself is a histamine releaser, no stereoselectivity being observed. In the presence of compound 48/80 it takes part in a non-stereoselective inhibitory reaction at low concentrations. Inhibition of histamine release by isoprenaline was antagonized by 10 or 100 microM propranolol except at the highest isoprenaline concentration (1 mM). Both atenolol and propranolol nullified the inhibitory activity of noradrenaline, but not the increased histamine release it induces at higher concentrations (at least when acting in conjunction with compound 48/80). When rat mast cells are purified through Percoll, a change in their response profiles is observed. Isoprenaline and adrenaline by themselves elicit non-specific release of histamine; with compound 48/80, release is additive in the case of isoprenaline and supra-additive in the case of adrenaline. Results point to the loss of beta-adrenergic inhibitory activity after purification.  相似文献   

20.
Characteristics of histamine (Hi) and 5-hydroxytryptamine (5-HT) release from rat peritoneal mast cells in response to the polypeptide adrenocorticotropin (ACTH) were studied. During a 15 min incubation at 37 degrees C, ACTH evoked Hi as well as 5-HT release from rat mast cells at concentrations of 1 X 10(-4) M-1 X 10(-3) M. The release was dose-dependent and very rapid. After 15 sec the amount of the amines released was the same as after 4.5 min. In most experiments, the percentage of Hi release was slightly but significantly higher than the percentage of 5-HT release. Hi and 5-HT release induced by ACTH also took place in a calcium-free medium. However, the release of the amines was decreased when calcium was omitted. Comparison of the effects of ACTH, compound 48/80 and substance P on mast cell secretion showed that ACTH is about 100 times less active then substance P which was in turn about 100 times less active than compound 48/80. When both ACTH and compound 48/80 were used together as liberators , the release was significantly higher than with either liberator alone. Our results indicate that there are receptor sites for the endogenous polypeptide ACTH on the mast cell membrane which mediate Hi and 5-HT release. This release was found to resemble that evoked by the basic secretogogue compound 48/80 but in some aspects to be different from that evoked by substance P.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号