乌拉坦升高小鼠血糖机制的研究

A Study of Urethane-induced Hyperglycemia in Mice

目的研究尾静脉或腹腔注射麻醉剂量乌拉坦或戊巴比妥钠对空腹雄性小鼠血糖水平的影响及其可能的作用机制。方法①雄性昆明小鼠80只,随机分为8组,每组10只。前3组尾静脉注射乌拉坦1.0 g.k-g1,给药后15,30,60 m in时取血测定血糖值;第4组注射等量0.9%氯化钠溶液为对照组;其余4组中的3组尾静脉注射戊巴比妥钠40 mg.kg-1,给药后15,30,60 m in时取血测定血糖值,第8组注射等量0.9%氯化钠溶液为对照组。所有小鼠均于取血后立即取肌肉和肝脏组织测糖原含量。②取小鼠80只,观察腹腔注射乌拉坦1.0 g.kg-1或戊巴比妥钠40 mg.kg-1对血糖的影响,动物分组及取血同前,仅测定血糖变化。③取小鼠20只,随机分为两组,给药组尾静脉注射乌拉坦1.0g.kg-1,对照组注射等量0.9%氯化钠溶液,注射30 m in后取血测定红细胞、白细胞和血小板计数。结果静脉注射麻醉剂量乌拉坦后15 m in小鼠血糖增高48.4%;腹腔注射同等剂量乌拉坦后15 m in小鼠血糖水平升高204%,60 m in时仍升高59.3%。两种给药途径给予麻醉剂量戊巴比妥钠后,小鼠血糖水平均无明显改变。静脉注射乌拉坦和戊巴比妥钠后,肝糖原含量显著升高,肌糖原含量无明显改变。与对照组比较,静脉注射乌拉坦对红细胞、白细胞、血小板数目均无显著性影响。结论腹腔注射乌拉坦诱发的小鼠高血糖反应明显强于静脉注射,提示乌拉坦可能通过局部刺激作用加重其高血糖反应。

Objective To study the effects of urethane and pentobarbital sodium in anesthetizing doses administered intravenously or intraperitoneally on the blood glucose levels in mice and the underlying mechanisms. Methods ①80 male Kunming mice were randomly divided into 8 equal groups. Mice of group 1 to group 3 were given each 1.0 g·kg^-1 of urethane via the caudal vein. Blood samples were taken 15,30 and 60 min after the urethane injection for the determination of glucose concentration with the glucose oxidase method. Mice of group 4 , serving as control, were given each an IV injection of equivalent amount of 0. 9 % sodium chloride （NS） solution. Blood samples were taken as well for glucose determination as described. Mice of group 5 to group 7 were given each an Ⅳ injection of 40 mg·kg^-1 of pentobarbital solution. Mice of group 8, serving as control, were given each an IV injection of equivalent amount of 0. 9 % NS. Blood samples were taken from these mice 15,30 and 60 min after the injection for blood glucose determination. Muscle and liver tissues were taken from all the mice of these 8 groups immediately after the collection of blood samples for the determination of glycogen with the anthrone method. ②80 male mice were randomly divided as described in experiment ①. Except for mice of the control groups, these animals were given each an intraperitoneal injection of 1.0 g·kg^-1 of urethane or 40 mg·kg^-1 of pentobarbital solution. Blood samples were taken for glucose determination as described in experiment ①. ③ 20 mice were randomly divided into 2 equal groups, mice of the trial group were given each 1.0 g·kg^-1 of urethane Ⅳ and those of the control group were given each equivalent amount of NS Ⅳ. Blood samples were taken 30 min after the injections for the counting of red blood cells, white blood cells and blood platelets. Results Blood glucose concentration was increased by 48.4 % 15 min after the intravenous administration of urethane at an anesthetizing dose. In contrast, blood glucose concentration was increased by 204 % and 59. 3 % 15 min and 60 min, respectively, after the intraperitoneal injection of urethane at that same anesthetizing dose. Intravenous or intraperitoneal administration of pentobarbital sodium at anesthetizing doses did not bring about apparent changes in the blood glucose concentration of the animals. The glycogen content of the liver was significantly increased after the IV injection of urethane or pentobarbital sodium, while the content of muscle glycogen was not apparently affected. Intravenous administration of urethane did not change the countings of red blood cells, white blood cells or blood platelets significantly as compared with results of the controls. Conclusion Intraperitoneal administration of urethane was shown to induce a hyperglycemia far more pronounced than that caused by intravenous administration of the drug at the same dose, suggesting that a local stimulating effect exerted by urethane may aggravate the hyperglycemia in mice.