Dahl盐敏感性大鼠体外循环模型的建立

A model of cardiopulmonary bypass in Dahl salt-sensitive rats

目的建立Dahl盐敏感性（Dahl／SS）：赶鼠体外循环（CPB）模型。方法雄性sD大鼠7只，14～16周龄，CPB时间120min作为阳性对照组（I组）；雄性Dahl／SS大鼠10只，14～16周龄，采用随机数字表法，将其随机分为2组：CPB时间120min组（Ⅱ组，n=5）和CPB时间75min组（HI组，n=5）。Dahl／SS大鼠先低盐饮食喂养，CPB前4周改为高盐饮食喂养。吸入异氟醚麻醉诱导后，经口气管内插管，接呼吸机行机械通气。右颈内静脉和尾动脉插管分别作为静脉引流和动脉回流通道，血液经定制的微型氧合器氧合。分别于CPB前、CPB30、60min、CPB结束后30、90min（T1-5）时采集动脉血样，进行血气分析，并测定血糖浓度；分别于上述时点记录MAP。计算各时点MAP和血糖的变化率，记录CPB结束后7d内大鼠的生存情况。结果3组间动脉血气分析指标比较差异无统计学意义（P〉0．05）。与I组比较，Ⅱ组T2。；时MAP变化率升高，T4时血糖变化率升高（P〈0．05）；与Ⅱ组比较，Ⅲ组T2，时MAP变化率降低，T4时血糖变化率降低（P〈0．05）。I组、Ⅱ组和Ⅲ组CPB结束后7d内生存率分别为7／7、1／5和4／5，Ⅱ组生存率最低（P〈0．05）。结论Dahl／SS大鼠CPB维持75min是可行的。

Objective Dahl salt-sensitive （Dahl/SS） rats are hereditary salt-sensitive hypertensive rats. Its pathogenesis is similar to that of human primary hypertension. CPB established in Dahl/SS rats provides an animal mode] for the study of CPB in patients with primary hypertension. Methods Male 14-16 weeks old Dahl/SS rats weighing 360-390 g were fed with high salt （8 % NaC1） diet for 4 weeks before the experiment. Ten Dahl/SS rats were randomly divided into 2 groups （n = 5 each） according to the CPB time： groups H and ~ underwent CPB for 120 and 75 rain respectively. Another 7 male 14-16 weeks old ordinary SD rats weighing 410-490 g undergoing CPB for 120 min were used as control group （group I ） . Anesthesia was induced with isoflurane inhalation. Orotracheal intubation was performed. The animals were mechanically ventilated. Right jugular vein and tail artery were cannulated for venous drainage and arterial inflow from CPB circuit. Blood was oxygenated with a customized mini-oxygenator. Blood gases were analyzed and blood glucose concentration was determined. MAP was recorded before （baseline） and at 30 and 60 min of CPB and 30 and 90 min after CPB. The rate of changes in MAP and blood glucose concentration and survival rate at 7 d after termination of CPB were recorded. Results There was no significant difference in blood gases among the 3 groups. The rates of change in MAP and blood glucose concentra- tion were significantly higher during and after CPB in Dahl/SS rats than in control SD rats in a duration of CPB dependent manner. The survival rate at 7 d after CPB was 7/7 （in group I ） , 1/5 （in group 11 ） and 4/5 （in group III ） respectively. Conclusion A model of 75 min CPB is established successfully in Dahl/SS rats.