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1.
Summary The ATP content of rat peritoneal mast cells has been studied in relation to histamine release induced by compound 48/80 and antigen-antibody (anaphylactic) reaction in vitro. When the ATP content of actively sensitized mast cells was reduced to different levels by oligomycin, a good correlation was obtained between the ATP levels and the amounts of histamine released by the anaphylactic reaction. A similar linear relation has previously been demonstrated between the ATP levels of mast cells and histamine release induced by compound 48/80. The ATP content of mast cells was also studied at different intervals after the exposure of the cells to antigen or compound 48/80. No significant change in the ATP content was observed in untreated mast cells during the short period when histamine release occurs. If, however, the mast cells were preincubated with oligomycin or 2-deoxyglucose to reduce the rate of ATP synthesis while a large part of the histamine release remained unaffected—a decrease in the ATP content could be demonstrated in close time relation to both anaphylactic and compound 48/80-induced histamine release. The observations indicate an increased utilization of ATP in mast cells during the release process.  相似文献   

2.
1. Iopanoic acid and iophenoxic acid were potent inhibitors of compound 48/80-induced histamine release from rat peritoneal cell suspensions rich in mast cells and caused a parallel dose-related reduction in ATP content of these cells. 2. Lignocaine was less potent and ouabain and probenecid were ineffective in inhibiting histamine release and reducing cellular ATP content. 3. Various drugs can inhibit 48/80-induced histamine release from rat peritoneal cells and this activity may result from depletion of cellular ATP. It is apparent that little structural specificity is required for activity in this cell system.  相似文献   

3.
Abstract: Antimycin A (0.2 μM) reduced the ATP content in isolated rat mast cells to 25–30 % of the original value. Pyruvate (4.9 mM) did not restore the ATP content in antimycin A-treated cells, indicating a complete block of oxidative ATP production. 82–97 % of the glucose which disappeared from suspensions of mast cells in the presence of antimycin A was recovered as lactate. Therefore, the rate of lactate accumulation in suspensions of antimycin A-treated cells was used as a measure of the cellular ATP production rate. Maximal accumulation occurred with 1.1 mM glucose. Incubation with glucose (0.51 mM) for 2.5 min. completely restored the ability of mast cells pretreated with antimycin A to release histamine when exposed to compound 48/80. Concomitantly, the ATP content in the cells was restored to a steady-state level of about 75 % of the original value. 0.29 mM glucose partially restored the histamine release as well as the ATP level whereas 0.13 mM glucose did not affect either of these parameters. The turnover time of ATP at steady-state was about 30 sec. with all three concentrations of glucose, which indicates that the rate of ATP utilization by the cells is directly proportional to the ATP content. The present study supports the view that histamine release induced by compound 48/80 is dependent on the ATP content in the mast cells at the time of exposure to compound 48/80.  相似文献   

4.
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   

5.
Compound 48/80 ( compd 48/80)-induced histamine secretion from rat mast cells was inhibited almost completely by pretreatment of the cells at 37 degrees with 25 microM arachidonic acid in the presence of 1.8 mM Ca2+. As the Ca2+ concentration was reduced below 1.8 mM, 25 microM arachidonic acid became less inhibitory and, then, progressively more stimulatory for histamine release with or without compd 48/80. No additive effect on histamine release was obtained by combining compd 48/80 and arachidonic acid. Pretreatment of mast cells with lidocaine, an inhibitor of Ca2+ binding to phospholipid, or with nordihydroguaiaretic acid, an inhibitor of Ca2+ flux and lipoxygenase, stimulated arachidonic acid-induced histamine release. Arachidonic acid also inhibited a compd 48/80-induced spike increment of intracellular 45Ca2+ uptake and a decrease of total 45Ca2+ uptake by 45Ca2+-preloaded mast cells. Arachidonic acid and Ca2+ also suppressed melittin-induced histamine release and compd 48/80-induced release of radioactivity from mast cells preloaded with [3H]arachidonic acid. These results suggest that exogenous arachidonic acid or its metabolite(s) may interact with membrane-associated Ca2+, disturbing Ca2+ availability for the trigger mechanism of compd 48/80-induced histamine release or inhibiting the subsequent metabolism of arachidonic acid via the lipoxygenase pathway to form active metabolites involved in the histamine liberating mechanism.  相似文献   

6.
The effects of butyl 3'-(1H-tetrazol-5-yl)oxanilate (WP-833), a new antiallergic drug, on its ability to inhibit histamine release from both peritoneal mast cells and lung fragments of rats were investigated. WP-833 inhibited in a dose-dependent fashion immunoglobulin E (IgE)-mediated histamine release from mast cells. Such potent inhibition was observed in glucose-free as well as complete Tyrode's solution but neither in Ca2+-free nor D2O-supplemented Tyrode's solution. In addition, WP-833 significantly increased intracellular cyclic adenosine monophosphate (AMP) levels in purified mast cells. On the other hand, WP-833 inhibited compound 48/80-but not calcium ionophore A23187-induced histamine release from normal mast cells. Also both IgE- and IgG-mediated histamine release from lung fragments were inhibited by WP-833. WP-833 showed non-competitive inhibition of cyclic AMP-dependent phosphodiesterase derived from lung preparations.  相似文献   

7.
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   

8.
Alpha-chymotrypsin (CT) was modified chemically and physically by the treatments with diisopropyl fluorophosphate, L-(1-tosylamide-2-phenyl) ethylchloromethylketone, hydrogen peroxide and heat. After these treatments, CT lost or decreased both the enzymic activity and ability of releasing histamine from rat mast cells. Ca++ was essential for histamine release by CT, while it enhanced only slightly the enzymic activity. Process of histamine release by CT could be separated into two stages: CT-dependent but not Ca++-dependent, and Ca++-dependent but not CT-dependent. The activated state of mast cells produced by CT decayed rapidly at 37 degrees C in the absence of Ca++, but these cells responded to Ca++ by adding CT once again, suggesting reconstitution of cell membrane structure affected by CT. Isoproterenol, epinephrine, prostaglandin E1, and dibutyryl-cyclic AMP (0.01-0.1 mM) did not inhibit release of histamine induced by CT. Neither theophylline (0.01-0.1 mM) alone nor the combinations of these cyclic AMP-active agents with theophylline inhibited the release of histamine. But, in the presence of papaverine (0.01-0.1 mM) a marked, dose-dependent inhibition was observed. These data suggest that 1) release of histamine by CT from rat mast cells is causally related to its hydrolytic activity, 2) this activity causes a reversible change on mast cell membrane which probably facilitates Ca++-influx through the cell membrane, and 3) there are subtle differences among CT, compound 48/80 and antigens concerning the effect of cyclic AMP-active agents in histamine-releasing mechanisms in mast cells.  相似文献   

9.
The effect of the local anaesthetics lidocaine, procaine and tetracaine on compound 48/80-induced histamine release from isolated rat mast cells has been investigated. They inhibited histamine release in a dose-dependent manner; at a concentration of 20 mM there was almost total inhibition of histamine release by lidocaine and about 75% inhibition by procaine. Tetracaine exerted a biphasic effect: at concentrations below 1 mM it inhibited, but at concentrations above 1 mM it potentiated histamine release. The inhibitory effect of lidocaine on compound 48/80-evoked histamine release was dependent upon the time of preincubation of mast cells with this anaesthetic and it persisted after washing the cells and resuspension in a lidocaine-free medium. An increase of calcium ions antagonized the inhibitory action of lidocaine. These results can be explained by (1) blockade of membrane receptors for calcium binding which leads to a decrease in intracellular calcium concentration and (2) increase of cellular cyclic AMP content which subsequently inhibits the releasing process.  相似文献   

10.
Polymorphonuclear cells (PMN) are the dominating inflammatory cell population in acute tissue injury and contribute to host-defence mechanisms by formation and release of chemical mediators. The aim of the present study was to investigate whether chemoattractant-induced PMN stimulation can be synergistically antagonized by vasodilatory prostaglandins and nitric oxide (NO), both being formed by the vasculature in inflamed areas. PGE1 (10 nM?10 μM) inhibited concentration-dependently formyl-methionyl-leucyl-phenylalanine (fMLP)-induced β-glucuronidase and oxygen radical (O2) release from human PMN. The NO donor linsidomine (100 μM) was ineffective, but significantly enhanced PGE1 effects on oxygen radical generation and enzyme release. The non-selective phosphodiesterase inhibitor 3-isobutyl-1-methylxanthine (IBMX) (0.5 mM) potentiated PGE1 effects on all parameters measured. The combination linsidomine (100 μM) plus IBMX (0.5 mM) did not additionally reduce β-glucuronidase release, but abolished fMLP-stimulated O2 generation. There was a stimulation of cAMP formation by PGE1 but not by linsidomine, both in the absence and presence of IBMX. It is concluded that the effects of linsidomine on PMN function and its synergism with PGE1 are not tightly correlated with total cAMP accumulation. Alternatively, the inhibition of O2 generation by linsidomine may be related to its ability to modulate the activation of the NADPH oxidase system or to scavenge free oxygen radicals.  相似文献   

11.
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   

12.
E S Assem 《Agents and actions》1982,12(1-2):203-206
The uptake of 14C-ring labelled histamine and histidine was studied in human and guinea-pig leucocytes, and in rat peritoneal mast cells. Histamine uptake by sensitized human leucocytes was partly released by antigen or anti-IgE challenge, suggesting that histamine is taken up by the same cells that synthesize and secrete that amine, i.e. basophils. Histamine antagonists, particularly of the H2-subclass, had an inhibitory effect, but histamine agonists had a relatively small and inconsistent effect. Adrenoceptor stimulants and phosphodiesterase inhibitors produced small effects, but dibutyryl cAMP at a concentration of 4-10 mM consistently increased histamine uptake by more than 100% during a 30 min incubation. By contrast, ATP exerted an inhibitory effect, starting at a concentration of 0.2 mM and reaching a maximum (90% inhibition) at 10 mM. Histidine uptake was inhibited by ATP and slightly stimulated by cAMP. Propranolol caused stimulation of histamine uptake and inhibition of histidine uptake at micromolar concentrations. These results suggest that the uptake of histamine is not due to simple diffusion. Although it does not contribute significantly to total cell histamine content or to the removal mechanism of extracellular histamine, it may contribute to the auto-regulatory processes modulating histamine release, synthesis and metabolism. It may also have a significant effect on the extracellular level of histamine, under the influence of drugs or in pathological states.  相似文献   

13.
14.
The sesquiterpene lactones isolated from Geigeria were found to be incapable of inducing rat peritoneal mast cell degranulation at levels of 0.3-1.6 mM. The sulphydryl reagent, N-ethylmaleimide, too was unable to trigger mast cell secretion. Instead, it was observed that these compounds inhibited the release of histamine induced by Compound 48/80. Pretreatment of the lactones and N-ethylmaleimide with the amino acid, L-cysteine, reduced their inhibition ability of histamine release to a considerable extent, but not completely. Geigerin(V), which lacks an alpha-methylene group and the chemically prepared cysteine-adduct of dihydrogriesenin(I), were also capable of inhibiting mast cell secretion by Compound 48/80, but to a lesser extent.  相似文献   

15.
Mast cells stimulation activates degranulation process resulting in releasing of mediators, such as histamine. In this study, the effect of aqueous extract of sitagliptin, a selective dipeptidylpeptidase-4 inhibitor, on the mast cell-mediated allergic response was studied with the possible mechanisms of action, focusing on the histamine release and pro-inflammatory cytokine secretion in mast cells. Sitagliptin produced dose dependent inhibition in compound 48/80-induced systemic reactions. In addition, sitagliptin attenuated IgE-mediated skin allergic reaction. Sitagliptin dose-dependently reduced compound 48/80- and IgE-induced histamine release from mast cells. Sitagliptin decreased the secretion of pro-inflammatory cytokines, tumor necrosis factor-α, in mast cells. So, the finding of this study provides evidence that sitagliptin inhibits mast cell derived allergic reactions, and involvement of pro-inflammatory cytokine secretion in such effects.  相似文献   

16.
The effect of ouabain on the histamine secretion induced by compound 48/80 has been studied using rat peritoneal mast cells. Ouabain did not modify histamine release in the presence of millimolar concentrations of extracellular calcium. However, when mast cells were previously washed with a calcium-free buffer, ouabain strongly potentiated histamine release elicited by compound 48/80. The full potentiation of mast cell secretion by ouabain required 30 min preincubation before adding compound 48/80. It was inhibited by lanthanum and EGTA. Potassium deprivation mimicked the effect of ouabain. A 30 min preincubation time without potassium was also required. Potassium concentrations below 2.7 mM increased the effect of ouabain whereas higher potassium concentrations reversed this effect. The potentiation of compound 48/80-induced histamine release by ouabain or potassium deprivation was not immediately reversed by washing away ouabain or by adding potassium, respectively. The data confirm that sodium-potassium ATPase is involved, through a calcium-dependent process, in the regulation of histamine release from mast cells.  相似文献   

17.
The discovery of drugs for the treatment of allergic disease is an important subject in human health. Stimulation of mast cells starts the process of degranulation resulting in releasing of mediators, such as histamine. In this report, we investigated the effect of aqueous extract of Dracocephalum argunense Fisch. (Labiatae) (DAAE) on the mast cell-mediated allergic response and studied its possible mechanisms of action, focusing on the histamine release and pro-inflammatory cytokine secretion in mast cells. DAAE inhibited compound 48/80-induced systemic reactions and serum histamine release in mice. In addition, DAAE attenuated IgE-mediated skin allergic reaction. DAAE dose-dependently reduced IgE-induced histamine release from mast cells. The level of cAMP was transiently increased by treatment of DAAE. DAAE specifically blocked the phorbol 12-myristate 13-acetate (PMA) plus calcium ionophore A23187-induced p38 mitogen-activated protein kinase (MAPK) activation. DAAE decreased the secretion of pro-inflammatory cytokines, such as tumor necrosis factor-alpha and interleukin-6 in mast cells. Our findings provide evidence that DAAE inhibits mast cell derived allergic reactions, and involvement of cAMP for histamine release and p38 MAPK for pro-inflammatory cytokine secretion in these effects.  相似文献   

18.
We investigated the effects of hot-water extract from the root bark of Morus alba (HEMA) on anaphylactic reactions. Using in vitro and in vivo experiments, we examined whether HEMA could inhibit compound 48/80-induced systemic anaphylactic shock and anti-chicken gamma globulin (CGG) IgE-mediated rat peritoneal mast cell activation. HEMA significantly inhibited systemic anaphylaxis induced by the compound 48/80 in mice. HEMA also significantly inhibited the passive cutaneous anaphylaxis activated by anti-CGG IgE. HEMA had no cytotoxicity on rat peritoneal mast cells (RPMC). Moreover, HEMA dose-dependently inhibited mast cell degranulation, histamine release and calcium uptake into RPMC induced by the compound 48/80 or anti-CGG IgE. When HEMA was added, the level of intracellular cAMP in RPMC showed a transient and significant increase (5-fold) compared with that of control cells. HEMA also inhibited significantly the compound 48/80-induced cAMP reduction in RPMC. These results suggested that HEMA inhibits the compound 48/80- or anti-CGG IgE-induced mast cell activation and its inhibitory effects on mast cell activations were favorably comparable to disodium cromoglycate. And HEMA is a candidate for effective therapeutic tools of allergic diseases.  相似文献   

19.
1. The purpose of this study was to compare the actions of phorbol 12-myristate 13-acetate (PMA) and ionomycin on Na+/H+ exchange activation and histamine release to that of compound 48/80 in order to study the possible relationship between pHi and secretion of histamine in rat peritoneal mast cells. 2. Resting pHi in mast cells suspended in a bicarbonate-free physiological salt solution amounted to 6.73 +/- 0.05 (mean +/- s.d., n = 52). 3. PMA (20 nM) induced a substantial but rather slow increase in pHi. This response was very sensitive to inhibition by staurosporine, very sensitive to inhibition by 5-(N,N-hexamethylene)amiloride (HMA), insensitive to the absence of extracellular calcium (without EGTA), and sensitive to partial depletion of intracellular calcium with EGTA. 4. Ionomycin (1 microM) induced a biphasic change in pHi that was sensitive to inhibition by HMA, insensitive to staurosporine. In the absence of extracellular calcium using EGTA, the biphasic response disappeared, leaving only a slow, and diminished change in pHi. 5. The effects of ionomycin and PMA on pHi were additive. 6. Addition of the secretagogue compound 48/80 (1 microgram ml-1) increased pHi, substantially, delta pHi amounting to 0.29 +/- 0.05 pH-units (n = 4). The biphasic pHi-response was insensitive to the absence of extracellular calcium (without EGTA). The initial fast response in pHi was, however, inhibited by HMA, not staurosporine. 7. The finding that staurosporine and HMA each inhibited approximately half of the compound 48/80-induced pHi-response, whereas both inhibitors completely abolished the compound 48/80-induced pHi-response seems to indicate that two independent pathways for the activation of the Na+/H+ exchange were stimulated by compound 48/80. 8. The histamine release induced via both PKC activation (using PMA) and calcium (using ionomycin) were much larger than the sum of each activation pathway, whereas in the absence of extracellular calcium using EGTA, the histamine release in response to PMA and ionomycin was completely abolished. 9. The compound 48/80-induced histamine release was partially sensitive to inhibition by HMA (approximately 30% inhibition) and partially sensitive to inhibition by staurosporine (approximately 50% inhibition). Preincubation with staurosporine and HMA before stimulation with compound 48/80 showed the same degree of inhibition as observed after staurosporine alone, even though this combination of drugs completely inhibited the pHi-response. Furthermore, compound 48/80-induced histamine release was not dependent on the presence of extracellular calcium (with and without EGTA). 10. In spite of the similarities in second messenger pathways for pHi regulation and histamine release, it is, however, not very likely that these two processes are directly related. It is, however, possible, that an increase in pHi plays a permissive, rather than an essential role for histamine release in rat peritoneal mast cells. This hypothesis was supported by the finding that preincubation with the Na+/H+ exchange-inhibitor HMA inhibited 30% of the compound 48/80-induced histamine secretion.  相似文献   

20.
The present investigation was prompted by our previous finding that in the liver fluke, Fasciola hepatica, some phosphodiesterase inhibitors, instead of potentiating the rise in endogenous cAMP caused by 5-hydroxytryptamine (5-HT), antagonized it. Papaverine, 1-ethyl-4-(isopropylidenehydrazino)-1H-pyrazolo-(3,4-b)-pyridine-5-carboxylic acid, ethyl ester, HCl (SQ 20009), 6,7-dimethyl-4 ethyl-quinazoline (Quazodine) and caffeine inhibited 5-HT-activated adenylate cyclase from particulate fractions of the liver fluke. This may explain their in vivo antagonism to the 5-HT-mediated rise in endogenous cAMP levels. Isobutylmethylxanthine (IBMX), which did not antagonize the 5-HT effect in vivo, did not inhibit 5-HT-activated adenylate cyclase in fluke particles. None of the above compounds inhibited the NaF-activated adenylate cyclase. Kinetic studies showed that inhibition of 5-HT-activated adenylate cyclase by papaverine or SQ 20009 was not competitive with the substrate, ATP, or with GTP. While high levels of 5-HT decreased the degree of inhibition by papaverin and SQ 20009. the kinetics of inhibition does not appear to be strictly competitive.  相似文献   

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