恐惧应激对大鼠心血管系统及一般行为的影响

Influence of Fear Stress on Cardiovascular System and Behaviors in Rats

目的观察恐惧应激对大鼠血压、心率及一般行为的影响。方法采用条件恐惧应激模型,将64只成年雄性Wistar大鼠随机分为恐惧应激模型组、对照组。通过对大鼠恐惧行为的观察、自发活动试验的测定,动态观察两组大鼠在不同恐惧应激时期行为学方面的变化;通过无创尾动脉测压法,观察不同恐惧应激时程大鼠血压及心率的变化;采用放射免疫学方法测定大鼠在不同恐惧应激时程血清中肌钙蛋白I浓度的变化。结果恐惧组大鼠冻结时间显著高于对照组(t=5.700,P<0.01);恐惧应激组体重在第2周以后增加显著低于对照组(t=2.675,t=2.316;P<0.05;t=3.930,P<0.01);自发活动中恐惧应激组活动次数显著低于对照组(t=2.267,P<0.05;t=2.990,t=3.325;P<0.01;t=2.423,P<0.05);恐惧应激组自发活动中休息时间显著高于对照组(t=2.621,P<0.05;t=3.356,P<0.01;t=2.668,P<0.05;t=2.384,P<0.05);随着应激时程的增加条件恐惧应激组血压显著高于对照组(第2周t=2.887,P<0.05;第3周t=4.263,P<0.01;第4周t=4.414,P<0.01);恐惧模型组心率与对照组相比显著升高(第2周t=2.382,P<0.05;第3周t=1.996,P<0.05;第4周t=1.881,P<0.05);条件恐惧应激模型组大鼠血清cTnI浓度显著高于对照组(第1周t=2.147,P<0.05;第2周t=3.479,P<0.01;第3周t=3.402,P<0.01;第4周t=3.863,P<0.01)。结论条件恐惧应激对大鼠血压、心率、体重、一般活动、血清cTnI都有明显影响。

Objective To observe influence of fear stress on blood pressure,heart rate and behavior in rats.Methods The experiment was carried out with conditioned fear stress model,64 adult male wistar rats were divided into fear stress model group and control group.The behavior changes of the rats at different times of fear stress were observed by observing the fear behaviors and testing spontaneous activity,the changes of blood pressure and heart rate were observed by noninvasive manometry,the cardiac troponin I（cTnI） concentrations at different times of fear stress were measured by radioimmunoassa.Results The freezing time of conditioned fear stress model group was significantly higher than that of the control group（t=5.700,P0.01）;the body weight increase of conditioned fear stress model group was significantly lower than that of the control group after 2 weeks（t=2.657,P0.05;t=2.316,P0.05;t=3.930,P0.01）;the spontaneous activity of conditioned fear stress model group was significantly lower than that of the control group（t=2.621,P0.05;t=3.356,P0.01;t=2.668,P0.05;t=2.384,P0.05）;with the increase of stress time,the blood pressures of fear stress model group was significantly higher than those of the control group（week 2：t=2.887,P0.05;week 3：t=4.263,P0.01;week 4：t=4.414,P0.01）;the heart rates of conditioned fear stress group significantly increased than the control group（week 2：t=2.382,P0.05;week 3：t=1.996,P0.05;week 4：t=1.881,P0.05）;the serum cTnI of conditioned fear stress model was significantly higher than that of the contral group（week 1：t=2.147,P0.05;week 2：t=3.479,P0.01;week 3：t=3.402,P0.01;week 4：WTBX〗t=3.863,P0.01）.Conclusion Conditioned fear stress has effcts on blood pressure,heart rate,general activity,serum cTnI in rats significantly.