组胺能纤维在刺激内脏大神经升压反应中作用的实验研究

用乌拉坦麻醉家兔22只,研究组胺能纤维在刺激含交感节前纤维的内脏大神经的升压反应中的作用。结果:(1)用强度5V,波宽2ms,频率为80、40、20、10和5HZ的刺激分别刺激内脏大神经,其中以40和20Hz引起升压反应最大,其余的反应明显降低。频率与反应之间的关系不受抗组织胺药物的影响.(2)H_1受体拮抗剂(扑尔敏1mg/Kg)能明显加强刺激内脏大神经的升压反应:H_2受体拮抗剂(西咪替丁20mg/kg)使升压反应明显减弱。(3)不管给扑尔敏或西咪替丁的先后,即H_1和H_2受体均被阻断时,刺激内脏大神经的升压反应回复到对照水平。讨论了交感节前与节后纤维中组胺能纤维不同作用的可能原因.

Role of Histaminergic fiber in Pressor Response to Splanchnicus Major Nerve Stimulation in the Anesthetized Rabbit

The role of histaminergic fiber in preganglionic fibers of the sympathetic nerve wasstudied with 22 rabbits anesthetized with urethane.The results are as follows:1.Splanchnious major nerve (SMN) was stimulated by electricity at frequencies of 80,40,20,10 and 5 Hz respectively.The stimulation with electricity at frequences in the range of 20 to40 Hz results in the greatest pressor response.The pressor responses to the stimulation withelectricity at frequencies higher than 40HZ and lower than 20Hz decreases significantly.thecorrelation between the electricity frequencity used for stimulation and pressor responseswas not influenced by lantihistamine drugs.2.the pressor responses to SMN stimulationare increased by H_1 receptor antagonist(chlorphenicamine 1mg/kg) significantly.3.It does not matter whether cimetidine or chlorphenicamine is given first i.e.when H_1 andH_2 receptors are blocked the pressor responses induced by electrical stimulation of theSMN restore to its control level.4.The different effects of hitamine has been discussed.