心梗大鼠离体心脏的动作电位和不应期电生理研究

目的对比观察正常大鼠和心梗大鼠离体心脏动作电位和有效不应期的特点。方法用离体灌流吸附电极记录单向动作电位,常规电生理方法测量最大动作电位幅度(APA)、复极90%(MAP90)、复极50%(MAP50)、复极20%(MAP20)、有效不应期(ERP)。结果(1)和正常大鼠相比,心梗大鼠离体心脏左心房电生理参数MAP90(56.3±2.7vs.64.5±8.7,P<0.05)显著延长,ERP MAP90(0.89±0.2vs.0.78±0.3,P<0.05)减小,基础周期为250ms;右心室的电生理参数MAP90(67.6±14.1vs.134.1±26.7,P<0.001),ERP(55.0±3.53vs.69.0±8.9,P<0.05)明显延长,ERP MAP90(0.79±0.1vs.0.60±0.1,P<0.05)减小,基础周期为250ms;左心室的电生理参数MAP90(87.2±15.7vs.168.8±31.2,P<0.001)也呈显著延长,ERP(59.0±4.2vs.90.0±17.7,P<0.001),ERP MAP90(0.65±0.081vs.0.54±0.090,P<0.05)呈显著减小基础周期为250ms;(2)与正常大鼠相比,心梗大鼠的MAP90离散度(LVMAP90-RVMAP90)(17.0±6.5vs.51.4±28.7,P<0.001)]、ERP离散度(LVERP-RVERP)(4.0±2.2vs.20.0±7.9)P<0.001]显著增加,基础周期为250ms。结论心梗大鼠心脏不同部位的MAP的复极时间都显著性延长,MAP90和ERP离散度增加,这些电生理特点是促进折返形成、造成心律失常的主要原因。

An Electrophysiological Study on Effective Refractory Period(ERP)and Monophasic Action Potential(MAP)in Myocardial Infarction Rats

Objective To detect the activity of PLA2 and the content of PGE2 at local chronic compres- sion injury in rat spinal cord. Methods Biochemical activity method was used to detect the activity of PLA2. Radio-immunity method was used to detect the content of PGE2. Results (1) The activity of PLA2: The activity of PLA2 in experimental groups was increased after spinal cord compression, especial in the moderate compression group. There was significant difference (P<0.01) of the activity of PLA2 between the moderate compression group and the Sham-operated group. There also existed significant different (P<0.05) of the activity of PLA2 between severe, medium compression group and Sham-operated group. (2) The content of PGE2: There was significant difference (P<0.01) of the activity of PGE2 between the moderate, severe compression groups and the Sham-operated group. There also existed significant dif- ferent (P<0.05) of the activity of PGE2 between the mold compression group and Sham-operated group. And there existed significant different (P<0.05) of the activity of PGE2 between the mold compression group and the severe compression group. Conclusion After the chronic injury in rat spinal cord the continual inflammatory reaction can be produced, and it can make the continual injury in spinal cord more serious.