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排序方式: 共有1906条查询结果,搜索用时 171 毫秒
41.
目的 观察腹腔注射促肾上腺皮质激素(ACTH)对改进的完全佐剂性关节炎慢痛大鼠脊髓腰膨大,海马和纹状体内降钙素基因相关肽(Calcitonin gene-related peptide,CGRP)的影响。方法 (1)肾上腺摘除术。(2)CGRP放射免疫法。结果 (1)大鼠踝关节周围皮下注射自制的油包水型完全福氏佐剂成功地制备成一种全身反应较轻的慢性疼痛模型。(2)脊髓腰膨大中的CGRP在关节炎大鼠 相似文献
42.
Mild social stress abolishes the effects of isolation on anxiety and chlordiazepoxide reactivity 总被引:1,自引:0,他引:1
Rationale: Social isolation is anxiogenic and may change the effects of anxiolytic drugs. These effects are generally attributed to
”isolation stress”. However, isolation does not affect basal corticosterone levels; thus, it cannot be considered stressful.
On the contrary, isolation deprives animals of mild daily stressors that are inherent to social life. Since mild stressors
were shown to be anxiolytic in rats, it was postulated that short-term, repeated stressors may abolish the effects of isolation. Objectives: The aim of the present study was to investigate whether short-term, repeated, mild social stress can abolish the consequences
of isolation on anxiety and on the effects of chlordiazepoxide. Methods: Rats were housed in groups or in individual cages for 5 days (isolates). Half of isolates were daily submitted to the attacks
of a resident rat for 30 min per day, on 4 consecutive days (stressed isolates). On day 5, rats were treated either with vehicle
or with chlordiazepoxide and submitted to the elevated plus-maze test. Endocrinological consequences of experimental manipulations
were assessed in a different set of rats. Results: Plasma ACTH and corticosterone levels were similar in the three groups. Weight gain was higher, while plasma growth hormone
was lower in stressed isolates, both effects being consistent with a mild stress. Isolation had a clear anxiogenic effect.
This effect was completely abolished by the daily experience of social stress. Chlordiazepoxide had a significant anxiolytic
effect in all three groups. Its effects on classical plus-maze variables did not differentiate the three groups. However,
chlordiazepoxide decreased risk assessment activity only in isolates. Conclusions: The lack of appropriate endocrinological changes challenges the concept of ”isolation stress”. However, isolation was anxiogenic
in our study and it also induced subtle changes in the effects of chlordiazepoxide. It appears that mild daily stressors have
a protective effect against the effects of isolation.
Received: 23 May 1998 / Final version: 3 December 1998 相似文献
43.
Keck ME Hatzinger M Wotjak CT Landgraf R Holsboer F Neumann ID 《The European journal of neuroscience》2000,12(4):1487-1494
The ageing process has been shown to have a profound impact on the hypothalamo-neurohypophysial system (HNS) and the hypothalamo-pituitary-adrenocortical (HPA) axis in humans as well as in rodents. Therefore, in this study, the intracerebral and peripheral release patterns of both vasopressin and oxytocin have been studied in aged male Wistar rats under basal conditions and in response to ethologically relevant stressors, using intracerebral microdialysis and chronic blood sampling techniques, respectively. Approximately a twofold higher basal release of arginine vasopressin (AVP) within the hypothalamic paraventricular nucleus (PVN), but not within the supraoptic nucleus (SON), was found in aged rats, whereas basal oxytocin (OXT) release did not differ in comparison with young rats. With increasing age the rise in intra-PVN release of both AVP and OXT was blunted in response to forced swimming. In contrast, the intra-SON release of AVP was unrelated to age. Simultaneously recorded basal secretion of both AVP and OXT from the neurohypophysis into blood was increased in aged rats, with a blunted OXT response to swim stress. Opposed to that, plasma AVP levels remained unchanged in both groups. Basal plasma levels of corticotropin (ACTH) and corticosterone were elevated in aged rats, whereas stress-elicited ACTH and corticosterone responses were indistinguishable. These results indicate age-related changes in the HNS and HPA axis with an enhanced basal activity opposed to a blunted response to stressors with increasing age. The increased basal release of AVP within the PVN suggests a role of intracerebral AVP in age-associated alterations of HPA axis regulation. 相似文献
44.
45.
吗啡依赖及戒断大鼠糖皮质激素及其受体mRNA表达水平的改变 总被引:5,自引:0,他引:5
目的:研究慢性吗啡处理和吗啡戒断对大鼠血清中ACTH及其受体mRNA表达水平的影响。方法:利用放射免疫法测定吗啡依赖及戒断大鼠血清中ACTH及皮质醇的浓度;利用核酸分子杂交技术研究下丘脑糖皮质激素受体(GR)基因表达的改变情况。结果:(1)吗啡依赖组大鼠血清中ACTH及皮质醇的浓度明显低于对照组;戒断d1大鼠血清ACTH浓度仍明显低于对照组(P<0.01),但血清皮质醇的浓度则明显高于对照组(P<0.01);戒断d7大鼠血清ACTH浓度与对照组比较,无显著性差异(P>0.05),而血清皮质醇的浓度仍略高于对照组(P<0.05);(2)吗啡依赖组大鼠下丘脑GR基因表达水平下降(P<0.05),戒断组大鼠GR的基因表达均高于对照组,但无显著性差异(P>0.05)。结论:吗啡类物质的长期使用可以对下丘脑-垂体-肾上腺轴的激素分泌功能及GR的基因表达产生明显的抑制作用。 相似文献
46.
卡马西平对吗啡依赖大鼠戒断症状及ACTH的影响 总被引:2,自引:1,他引:2
目的 :观察卡马西平 (Carb)对吗啡依赖大鼠纳洛酮催促戒断症状的抑制作用及血清促肾上腺皮质激素(ACTH)水平的影响。方法 :剂量递增法皮下注射 (sc)盐酸吗啡 (Mor) ,建立大鼠吗啡依赖模型 ,腹腔注射 (ip)盐酸纳洛酮 1mg·kg- 1 催促 ,观察戒断反应并评分 ;免疫发光法测定血清ACTH水平。结果 :Carb 10 0mg·kg- 1 及 2 0 0mg·kg- 1 均可明显减轻大鼠戒断症状 (P <0 0 5 )。 10 0mg·kg- 1 剂量组的ACTH水平接近正常 ,低于Carb 2 0 0mg·kg- 1 组(P <0 0 5 )。结论 :适当剂量的卡马西平可有效控制吗啡依赖大鼠的戒断症状 相似文献
47.
目的 探讨在高原急性失血后不同灌注液扩容后血中促肾上腺皮质激素(ACTH),促甲状腺激素(TSH)含量的变化。方法 日本大耳兔28只,随机分为4组,每组7只。经股动脉放血,5min内使MAP降至5.3kPa,维持30rain开始输液治疗,分别输入生理盐水(NS),7.5%高张盐水(tiTS),6%贺斯(HAES)及不输液(对照组)。4组动物分别在失血前、失血后30min和输液治疗30min,由股动脉取血测定ACTH、TSH的含量。结果 4组中失血后30min与失血前比较ACTH下降(P〈0.05);对照组、NS组与失血前比较,ACTH下降更为显著(P〈0.01);输HTS组与失血前比较,ACTH恢复至术前水平(P〉0.05);输贺斯组与失血前比较,ACTH含量明显增加(P〈0.05);血浆TSH含量各组与失血前比较,均显著性增加(P〈0.01)。结论 高原失血后,ACTH明显降低,输注高张盐水和贺斯可刺激垂体前叶分泌ACTH。输注生理盐水无明显效果。而TSH含量在失血后和输注不同灌注液后均明显升高。表明:在高原失血后,机体对血中甲状腺素水平下降产生的应激反应比肾上腺素皮质激素下降更敏感。 相似文献
48.
Dhanalakshmi Angappan Jitendra K. Sahu Prahbhjot Malhi Pratibha Singhi 《European journal of paediatric neurology》2019,23(1):136-142
West syndrome is a distinct, infantile onset, epileptic encephalopathy, associated with poor neurodevelopmental outcome. The present study was designed as a randomized, open-label, pilot study to evaluate the safety, feasibility, and effectiveness of oral zonisamide therapy in comparison with adrenocorticotropic hormone therapy in infants with West syndrome. Thirty infants with West syndrome were randomized to receive treatment with either synthetic, intramuscular adrenocorticotropic hormone (30–60 IU) or oral zonisamide (4–25 mg/kg/day). The study participants had a long treatment lag and preponderance of male sex (90%). The primary effectiveness outcome measure was the cessation of epileptic spasms at 2 weeks of initiation of therapy and persistent till 6 weeks as per West Delphi consensus statement recommendations. Comparison of efficacies of zonisamide versus adrenocorticotropic hormone was as following: the cessation of epileptic spasms (27% vs. 40%, p = 0.70), resolution of hypsarrhythmia at 14 days (20% vs. 33%, p = 0.68) and resolution of hypsarrhythmia at 6 weeks (36% vs. 71%, p = 0.14). Overall, the study observed a poor efficacy of both adrenocorticotropic hormone and zonisamide therapy, which is probably due to long treatment lag and a high proportion of structural aetiology. However, oral zonisamide appeared to be safe and tolerable in the study. 相似文献
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