胰岛素治疗高血压动脉硬化性脑梗死的实验研究

Effects of insulin on cerebral infarction in hypertensive and arteriosclerotic rats

目的：观察胰岛素（ Ｉｎｓ）对高血压动脉硬化大鼠脑梗死的疗效。方法：５０ 只肾血管性高血压大鼠（ Ｒ Ｈ Ｒ）复制成大脑中动脉闭塞（ Ｍ Ｃ Ａｏ）模型，随机分４ 组： Ａ 组１２ 只（ Ｉｎｓ ２１ Ｕ／ｋｇ）， Ｂ组１２ 只〔 Ｉｎｓ ２１ Ｕ／ｋｇ＋ ５０％ 葡萄糖（２ ｇ／ｋｇ）〕， Ｃ组 １２ 只〔 Ｉｎｓ ４５ Ｕ／ｋｇ＋ ５０％ 葡萄糖（４ ｇ／ｋｇ）〕和 Ｄ组 １４ 只（生理盐水 ４ ｍ ｌ／ｋｇ）。各组均于 Ｍ Ｃ Ａｏ 后即注射胰岛素， Ｍ Ｃ Ａｏ 后 ４ 小时和２４ 小时检查神经功能，２４ 小时处死大鼠取脑，测大脑体积和梗死灶体积。结果： Ａ 组的血糖较其他组有统计学意义的下降（ Ｐ均＜ ００１）， Ｃ组的神经功能障碍评级、梗死灶体积及其与大脑体积的百分比的减少都有统计学意义（ Ｐ 均＜ ００１）， Ａ、 Ｂ、 Ｄ组间比较则无差异（ Ｐ 均＞００５）。结论：胰岛素对缺血脑组织具有不依赖于其降糖作用的直接保护作用， Ｒ Ｈ Ｒ Ｍ Ｃ Ａｏ 后注射胰岛素在较高剂量时才显示疗效，这可能与高血压致脑血管发生病变有关。

Objective:To observe the effects of insulin on cerebral infarction in hypertensive and arteriosclerotic rats.Methods:50 renovascular hypertensive rats (RHR) were subjected to middle cerebral artery occlusion (MCAo) and randomly allocated to four groups:group A ( n =12,insulin 2 1 U/kg),group B ( n =12,insulin 2 1 U/kg and 50% glucose 2 g/kg),group C( n =12,insulin 4 5 U/kg and 50% glucose 4 g/kg) and group D( n =14,normal saline 4 ml/kg).All rats were treated immediately following MCAo.Neurologic examinations were performed at 4 and 24 hours after MCAo in various groups.The rats surviving for 24 hours were killed to calculate cerebral volume and infarct volume.Results:The rats in group A had lower blood glucose levels than in group B,C,D(all P <0 01).The neurologic scores,total infarct volume and the percent of infarct volume in cerebral volume were significantly lower in group C than in the other groups and showed no significant differences among the other three groups.Conclusions:These results indicate that insulin exerts a direct protective effect on the ischemic brain independent of hypoglycemia.After MCAo,effects of high dose of insulin on RHR may be associated with cerebrovascular degeneration caused by hypertension.