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61.
组胺受体在枳实调节小鼠小肠运动中的作用   总被引:4,自引:0,他引:4  
目的:探讨枳实调节胃肠功能的作用机制,方法:采用活性碳末指示法,以小鼠在灌服不同药物一定时间后小肠碳末推进率为指标分析小肠的运动功能。结果:灌服枳实煎液可明显提高小鼠小肠碳末推进率,此效应可被H1受体拮抗剂苯海拉明阻断而不能被H2受体拮抗剂西米替丁阻断。结论:枳实增强小肠运动功能的作用与H1受体有关。  相似文献   
62.
嗜碱粒细胞组胺释放试验检测抗高亲和力IgE抗体及其受体   总被引:4,自引:0,他引:4  
目的 探讨慢性荨麻疹的发生机制。方法 用嗜碱粒细胞组胺释放试验,检测慢性特发性荨麻疹患者的血清组胺释放活性。结果 32例中,有15例(46.9%)患者血清组胺释放活性增高,提示FcεR1抗IgE自身抗体的存在。结论 部分慢性荨麻疹的发生与自身免疫机制有关。  相似文献   
63.
M. Pedersen    H. Permin    C. Jensen    P. Stahl  Skov  S. Norn  V. Faber 《Allergy》1987,42(4):291-297
Type I allergy against some common microorganisms was investigated in 14 patients with AIDS and 11 human immunodeficiency virus (HIV) antibody-positive homosexual men, and in a control group consisting of 13 heterosexual men without HIV antibodies. Basophil histamine release technique was used as a sensitive method to detect type I allergy against Candida albicans (CA), Herpes simplex virus type I (HSV-I) and cytomegalovirus (CMV). Of the 14 AIDS patients 11 (78%) showed significant histamine release when stimulated with CA, and HSV-I caused release in 10 (71%), whereas no response was obtained by CMV. In the group of HIV antibody-positive men only one released histamine when stimulated with CA and HSV-I and this patient also had lymphadenopathia. In contrast to these results, no release of histamine was obtained in the control group consisting of 13 heterosexual men. The histamine release caused by CA and HSV-I is mediated by an immunological reaction, since the release was abolished and regained by removal from and refixation to the cell surface of the cell-bound immunoglobulins. These results suggest an involvement of type I allergy as a pathogenetic co-factor in some infections in AIDS, and allergic type I reactions to CA and HSV-I might be an indicator for the presence of manifest AIDS.  相似文献   
64.
Neurotensin (NT)-like peptides in the CNS of the lamprey Lampetra fluviatilis were studied by radioimmunoassay (C-terminal specific NT antiserum), reverse-phase HPLC and immunohistochemistry. Multiple peaks of NT-immunoreactive (-ir) material were observed upon HPLC, of which a major peak eluted in the position of bovine NT. Immunofluorescence histochemistry showed that a monoclonal antibody recognizing the N-terminal (1 - 11) fragment of NT, as well as two polyclonal NT antisera labelled a large number of cell bodies in the periventricular area of hypothalamus, including the postinfundibular commissural nucleus and the ventral and dorsal hypothalamic nuclei. Additional groups of NT-ir cells were observed in the preoptic nucleus, the postoptic commissural nucleus, the mesencephalic tegmentum (L.fluviatilis), and in the spinal cord (L.fluviatilis and Ichtyomyzon unicuspis). Dense NT-ir fibre plexuses were present in the caudal hypothalamus, corpus striatum, ventral mesencephalon, and in the dorsal horn and lateral margin of the spinal cord. At the ultrastructural level the lateral spinal margin showed NT-ir terminal structures, which in most cases were not associated with synaptic specializations, although occasional synaptic contacts with unlabelled elements were found. The relation between NT-ir and monoamine-containing cells was examined with immunofluorescence double-staining, using antisera to tyrosine hydroxylase (TH), 5-hydroxytryptamine (5-HT), and histamine respectively. In the periventricular nuclei of hypothalamus numerous TH-, 5-HT-, as well as histamine-ir cells were located in close association with NT-ir cells, but none of the aminergic markers could be detected within NT-ir neurons. The chemical properties as well as the anatomical distribution of lamprey NT-like peptides show several similarities with those present in mammals, suggesting that NT-containing neuronal systems in the CNS developed early in vertebrate phylogeny.  相似文献   
65.
To clarify the role of endogenous histamine in learning and memory, the effect of -fluoromethylhistidine on active avoidance response in rats was studied. -Fluoromethylhistidine (20–100 mg/kg or 10–50 µg) significantly (P<0.05 orP<0.01) prolonged the response latency in active avoidance response when administered by either intraperitoneal or intracerebroventricular injection. These effects were dose-related and long lasting. A prolongation of the response latency induced by an intraperitoneal injection of -fluoromethylhistidine (100 mg/kg) was antagonized by intracerebroventricular injection of histamine (10 and 20 ng) in a dose-dependent manner. In addition, the acquisition of this response was retarded by a consecutive intracerebroventricular injection of -fluoromethylhistidine (50 µg), whereas histamine (100 ng) facilitated the response acquisition when administered by the same route. Both intraperitoneal (100 mg/kg) and intracerebroventricular injection of -fluoromethylhistidine (50 µg) significantly (P<0.05 orP<0.01) decreased the brain histamine content, especially in the hippocampus and hypothalamus. When -fluoromethylhistidine (50 µg) was injected intracerebroventricularly, there is a high correlation between a prolongation of the response latency and a decrease in histamine content of these brain areas. Based on these findings, it was concluded that an intimate relation may exist between a prolongation of response latency in the active avoidance response and a decrease in the brain histamine content; endogenous histamine may play an important role in learning and memory recollection in rats.  相似文献   
66.
Summary Rat brain cortex slices or synaptosomes preincubated with 3H-serotonin were superfused with physiological salt solution (which, in the case of slices, contained citalopram, an inhibitor of serotonin uptake), and the effects of histamine and related drugs on the evoked tritium overflow were studied.The electrically (3 Hz) evoked tritium overflow from slices was inhibited by histamine and the H3 receptor agonists R-(–)--methylhistamine and N-methylhistamine (pIC12.5 values: 6.41, 7.28 and 6.12, respectively), but not affected by the H1 receptor agonist 2-(2-thiazolyl)ethylamine and the H2 receptor agonist dimaprit (each at 10 mol/l). The concentration-response curve for histamine was shifted to the right by the H3 receptor antagonists impromidine, burimamide and thioperamide (apparent pA2 values: 7.45, 5.97 and 7.88, respectively); the concentration-response curve of serotonin for its inhibitory effect on the electrically evoked overflow was not affected by the three drugs (apparent pA2 values: < 5.5, < 5.5 and < 6.5). Given alone, impromidine, thioperamide and a low concentration of burimamide facilitated the electrically evoked overflow. In slices superfused with K+-rich, Ca2+-free solution containing tetrodotoxin throughout and in synaptosomes superfused with Ca2+-free solution, histamine inhibited the overflow evoked by introduction of Ca2+ (in synaptosomes, simultaneously with an increased amount of K+). In either tissue, the effect of histamine was counteracted by thioperamide.The results provide evidence that exogenous and probably also endogenous histamine inhibits serotonin release in the rat brain cortex via presynaptic histamine H3 receptors.Send offprint requests to E. Schlicker at the above address  相似文献   
67.
Summary In order to evaluate the time course of its effects, dimetindene maleate has been investigated in a histamine provocation model in man. Eight healthy male volunteers were treated i. v. with 4 mg dimetindene maleate or sodium chloride solution in a double blind, cross over study. Intracutaneous histamine injections were given at –1, 2, 5, 14, 17, 20, 23, 26, and 29 h following drug administration and the areas of flares and wheals were measured after 5, 10, 20, and 30 min. There was strong inhibition of the development both of flares and wheals, which was more pronounced for the former. Baseline adjusted areas under the curve differed significantly following drug and placebo treatment. The maximum effect was observed at 2 h.The mean residence time of the inhibitory effect was calculated to be 13 h compared to the mean residence time of dimetindene in blood of 5 h, which indicates a non-linear relationship between blood level and effect.  相似文献   
68.
We studied central mechanisms of antidepressants that affect feeding behavior in rats. The tricyclic compounds amitriptyline, doxepin and imipramine significantly induced feeding after their infusion into the third cerebral ventricle in the light phase, but the tricyclic, desipramine, and the dicyclic zimelidine, did not. Drinking was not affected by any compound tested. The relative order of potency in eliciting feeding was: amitriptyline and doxepin > imipramine > desipramine and zimelidine. To clarify the involvement of neuronal histamine in antidepressant-induced feeding, alpha-fluoromethylhistidine (FMH), a suicide inhibitor of histidine decarboxylase, was intraperitoneally administered before infusion of amitriptyline. FMH attenuated the amitriptyline's effect. Bilateral microinfusion of amitriptyline into the ventromedial hypothalamus or the paraventricular nucleus verified that these are loci for the modulation of feeding by amitriptyline. In the lateral hypothalamus, amitriptyline was less effective. These findings indicate that tricyclic antidepressants directly facilitate feeding, which is, at least in part, mediated by histamine in the hypothalamus.  相似文献   
69.
高效液相色谱柱后衍生法测定豚鼠鼻粘膜中组胺   总被引:1,自引:0,他引:1  
通过比较各种分析柱的分离效果 ,建立用离子交换柱分离 ,邻苯二甲醛 (OPA)柱后衍生荧光检测并分析豚鼠鼻粘膜组织中组胺的液相色谱方法 ,并对流动相的离子强度和pH进行了优化 ,确定以 40mmol·L- 1 pH 5 .5 0的柠檬酸钠缓冲液作为流动相为最佳条件。该方法的最低检测限为 5 0nmol·L- 1 ,回收率 >92 % ,线性范围为 5 0nmol·L- 1~ 5 0 0 μmol·L- 1 ,组胺的保留时间为 13min 12s,组胺峰面积的相对标准差 <3%。  相似文献   
70.
This study was conducted to assess the effect of sevoflurane on lung resistance and compliance, and its responsiveness to histamine. We studied eight dogs to compare the effect of sevoflurane, isoflurane, enflurane, and halothane on bronchoconstriction caused by histamine. Baseline values of pulmonary resistance (RL) and dynamic pulmonary compliance (Cdyn) were measured prior to administration of histamine. Histamine (2, 4, and 8 μg · kg−1) were administered iv, and the values of RL and Cdyn at the time of peak effect were recorded. Under 1 or 2 MAC anaesthesia, sevoflurane as well as the other three anaesthetics had no bronchoactive effects. The four anaesthetics, including sevoflurane, demonstrated inhibitory effect on increases in RL and decreases in Cdyn caused by histamine. At 1 MAC anaesthesia, % changes in RL caused by 2, 4, or 8 μg · kg−1 of histamine were 38 ± 11, 85 ± 21, or 132 ± 24% (mean ± SE) for halothane, and 65 ± 11, 132 ± 15, or 172 ± 19% for sevoflurane, respectively. Sevoflurane was less effective than halothane in preventing increases in RL. In preventing decreases in Cdyn, sevoflurane was less effective than halothane only at 8 μg · kg−1 of histamine under 1 and 2 MAC anaesthesia. There was no difference in attenuating effect on changes in RL and Cdyn between sevoflurane and isoflurane or enflurane. We concluded that sevoflurane was less potent than halothane in attenuating changes in RL and Cdyn in response to iv histamine. Cette étude a été réalisée dans le but d’évaluer les effets du sévoflurane sur la résistance et la compliance pulmonaires en réponse à l’histamine. Les effets du sévoflurane, de l’isoflurane, de l’enflurane et de l’halothane sur la bronchoconstriction induite par l’histamine sont comparés sur huit chiens. Avant l’administration d’histamine, on mesure les valeurs initiales de la résistance (RL) et de la compliance dynamique (Cdyn) pulmonaires. L’histamine (2, 4, 8 μg · kg−1) est administrée par la voie veineuse et les valeurs maximales de la RL et de la Cdyn sont enregistrées. Les quatre anesthésiques, dont le sévoflurane inhibent l’augmentation de la RL et la diminution de la Cdyn provoquées par l’histamine. A MAC 1 d’anesthésie, les pourcentages de changement de RL produits par 2, 4, ou 8 μg · kg−1 d’histamine sont respectivement de 38 ± 11, 85 ± 21, ou 132 ± 24% (moyenne + SD) pour l’halothane, et de 65 ± 11, 132 ± 15, ou 172 ± 19% pour le sévoflurane. Le sévoflurane est moins efficace que l’halothane pour prévenir les augmentations de RL. Le sévoflurane est moins efficace pour prevenir la diminution de Cdyn mais seulement à 8 μg · kg−1 d’histamine sous anesthésie à MAC 1 et 2. Le sévoflurane, l’halothane et l’isoflurane ne sont pas de différents pour amortir les changements de RL et Cdyn. Nous concluons que le sévoflurane est moins puissant que l’halothane pour diminuer la réponse à l’histamine de la RL et de la Cdyn.  相似文献   
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