鞘内注射和侧脑室注射异氟烷对小鼠抓力的影响

目的探讨异氟烷（Iso）的肌松作用部位。方法80只成年雌性小鼠按基础抓力、体重，采用分层随机区组设计分为鞘内注射异氟烷组（it组）和侧脑室注射异氟烷组（icy组），2组再各分为人工脑脊液（aCSF）组（aCSF0．04μl/g）、Isol（Iso0．02μl/g）、Is02（Iso0．04μl/g）、Is03（Iso0．08μl/g）4个亚组（每亚组n=10）。用YLS-13A大小鼠抓力测定仪测定各组给药前和给药后5、10、15、20、25、30min的抓力。结果①鞘内注射各Iso剂量组小鼠抓力均比aCSF组小（P〈0．05或P〈0．01）；②侧脑室注射各Iso剂量组与aCSF组小鼠抓力的差别无统计学意义（P〉0．05）；③it组小鼠抓力呈剂量依赖性减小（r=-0．793，P〈0．01，5min时）。结论鞘内注射异氟烷产生剂量依赖性肌松作用，而侧脑室注射异氟烷未产生明显肌松作用，提示异氟烷产生肌松作用的主要部位在脊髓。

The effect of intrathecal injection and intracerebroventricular injection of isoflurane on the grip strength in mice

Objective To explore the site of muscle relaxation under the effect of isoflurane （Iso）. Methods 80 mice were divided by basic grip strength and weight and by stratified randomization into intrathecal injection group （it group） and intracerebroventricular injection group （icy group）, with each group subdivided into 4 subgroups： artificial cerebral spinal fluid （aCSF） group （0.04 μl/g）, Isol （isoflurane 0. 02 μl/g） group, Iso2 （isoflurane 0. 04 μl/g） group, and Iso3 （ isoflurane 0. 08 μl/g） group （n = 10 each）. The grip strength was recorded before and after （5, 10, 15, 20, 25, 30 rain） isoflurane administration using the grip strength meter （YLS - 13A）. Results （1） In it group, the grip strength of Iso subgroups deceased compared to the aCSF subgroup （ P 〈 0. 05 or P 〈 0.01 ）. （2） In the icy group, the grip strength of Iso subgroups had no statistical difference as compared to the aCSF group subgroup （P 〉 0.05 ）. （3） The grip strength of it group deceased in a dose- dependent manner （r = -0. 793, P 〈0.01, 5 min）. Conclusion Intrathecal injection of isoflurane produced dose - dependent muscle relaxation effect, while intracerebroventricular injection of isoflurane did not produce evident muscle relaxation effect, indicating that spinal cord is the main site of muscle relaxation under the effect of isoflurane.