Jochem J
Department of Physiology, Silesian Medical University, Zabrze, Poland.
J Physiol Pharmacol. 2000 Jun;51(2):229-39.
The study was designed to determine the cardiovascular effects of histamine administered intracerebroventricularly (icv) in a rat model of volume-controlled haemorrhagic shock. The withdrawal of approximately 50% of total blood volume resulted in the death of all control saline icv treated animals within 30 min. Icv injection of histamine produced a prompt dose-dependent (0.1-100 nmol) and long-lasting (10-100 nmol) increase in mean arterial pressure (MAP), pulse pressure (PP) and heart rate (HR), with a 100% survival of 2h after treatment (100 nmol). The increase in MAP and HR after histamine administration in bled rats in comparison to the normovolaemic animals was 2.7-3.3- and 1.3-3.6-fold higher, respectively. Pretreatment with chlorpheniramine (50 nmol icv), H1 receptor antagonist, inhibited the increase in MAP, PP, HR and survival rate produced by histamine, while chlorpheniramine given alone had no effect. Neither ranitidine (50 nmol icv), H2 histamine receptor antagonist, nor thioperamide (50 nmol icv), H3 receptor blocker, influenced the histamine action, however, when given alone, both evoked the pressor effect with elongation of survival time. It can be concluded that histamine administered icv reverses the haemorrhagic shock conditions, and histamine H1 receptors are involved.
本研究旨在确定在容量控制型失血性休克大鼠模型中，脑室内注射组胺的心血管效应。抽取约50%的总血容量导致所有接受脑室内注射生理盐水的对照动物在30分钟内死亡。脑室内注射组胺可使平均动脉压（MAP）、脉压（PP）和心率（HR）迅速出现剂量依赖性（0.1 - 100 nmol）升高且持续时间长（10 - 100 nmol），给药后2小时100 nmol组胺组的存活率为100%。与血容量正常的动物相比，放血大鼠注射组胺后MAP和HR的升高分别高2.7 - 3.3倍和1.3 - 3.6倍。用H1受体拮抗剂氯苯那敏（脑室内注射50 nmol）预处理可抑制组胺引起的MAP、PP、HR升高及存活率增加，而单独给予氯苯那敏则无作用。H2组胺受体拮抗剂雷尼替丁（脑室内注射50 nmol）和H3受体阻滞剂硫代哌酰胺（脑室内注射50 nmol）均不影响组胺的作用，然而，单独给予时，二者均可引起升压效应并延长存活时间。可以得出结论，脑室内注射组胺可逆转失血性休克状态，且组胺H1受体参与其中。
