脊髓损伤大鼠动脉电生理的变化及丙泊酚的干预作用

目的探讨大鼠高位脊髓损伤(SCI)慢性期腹主动脉对Ca2 、K 收缩力改变及丙泊酚的干预作用。方法16只大鼠随机均分为两组:脊髓T4损伤组(SCI组,咬除T4椎板,横切T4脊髓),假手术组(只暴露脊髓,不进行横切)。取大鼠腹主动脉,测定血管环对Ca2 、K 敏感性以及丙泊酚的反应性。结果与假手术组相比,SCI组大鼠腹主动脉血管环对Ca2 反应性升高(P<0.05,P<0.01),量效曲线左移,Emax增大(P<0.01);30、60mmol/LKCl刺激下,SCI组血管环收缩力较大(P<0.01);与假手术组相比,SCI组大鼠血管环对丙泊酚的舒张作用更敏感(P<0.05,P<0.01),量效曲线左移,Emin减小(P<0.01)。结论血管对Ca2 、K 等反应性升高可能是高位SCI大鼠腹主动脉高反应性的原因;SCI大鼠血管对丙泊酚的舒张作用更为敏感。

Electrophysiological change of aorta in spinal cord injured rat and influence of propofol on it

Objective To observe the change of vascular reactivity of chronically spinal cord injured rat abdominal aorta to Ca 2 ,K and the infuence of propofol on vascular reactivity.Methods Sixteen rats were divided into two groups at random:sham-operated group (the fourth thoracic spinal cord was exposed but not transected) and the fourth thoracicspinal cord transection group.Then abdominal aorta was adopted to assay the sensitivity to K ,Ca 2 and propofol by isolated organ perfusion system. Results Compared with sham-operated rat abdominal aorta, spinalized rat abdominal aorta reactivity to Ca 2 ,K was significantly higher(P<0.05,P<0.01),the dose effect curve shifted to the left,Emax augumented.Propofol had a stronger effect on vascular relaxation of spinalized rats than that of sham-operated rats (P<0.05, P<0.01), the dose effect curve shifted to the left,Emin diminished (P<0.01).Conclusion Vascular hyperreactivity to Ca 2 ,K may be one of the mechanisms of abdominal aorta hyperreactivity of chronically spinalized rats.Spinalized rat aorta is more sensitive to propofol than sham-operated rat aorta.