甲醛致兔窦房结损伤模型的建立

Establishment of formaldehyde-induced sinoatrial node damage model in rabbits

目的建立甲醛诱导的兔窦房结损伤模型。方法采用40%甲醛溶液损伤兔窦房结,检测心率、窦房传导时间、窦房结恢复时间和校正窦房结恢复时间等指标,比较不同损伤方法、损伤程度、损伤持续时间等,并采用阳性药对模型进行验证。结果 （1）损伤方法：湿敷法可通过时间及面积大小控制损伤程度;滴注法创伤小,可通过甲醛量来控制损伤程度,但易造成窦房结周围组织损伤;（2）损伤程度和维持时间：心率下降百分率小于基础心率的30%时,模型维持时间小于7 d;下降至基础心率的30%~60%时,模型维持时间可达70 d;下降大于60%基础心率的模型动物死亡率较高;（3）阳性药物的验证：阿托品和心宝丸均增加窦房结损伤模型心率,改善窦房结功能的作用。结论甲醛湿敷法建立兔窦房结损伤模型较滴注法可靠性更高,损伤程度宜将心率下降百分率控制在基础心率30%至60%之间,模型维持时间长且动物死亡率低。

Objective To establish formaldehyde-induced sinoatrial node damage model in rabbit. Methods40% formaldehyde were used to damage the sinoatrial node area of rabbits. The parameters including heart rate,sinoatrial conduction time,sinus node recovery time,and the corrected sinus node recovery time were measured after formaldehydeindeced damage. The diferences of the methods,degrees and duration of formaldehyde-indeced damage were compared,and the reabilities of models were confirmed by positive control drug in the experiments. Results（ 1） Damage method： In formaldehyde wet compressing method,the damage degree can be controled by regulating the compressing timing and area.Comparing to the former,the less injuries was caused and the damage degree could be controlled by regulating the drip speed of formaldehyde in the formaldehyde drip method; but it tends to injure the surrounding tissue of the sinus node.（ 2）Damage degree and mantainance of the model： the damages only maintained less than 7 days,when the percentage of heart rate decreased less than 30% of basic heart rate,and its lasted more than 70 days,when the percentage of heart rate decreased to 30% ~ 60% of basic heart rate,but the heart rate decreased more than 60% of basic heart rate would lead tohigher death rate.（ 3） Verification of positive drugs： both atropine and xinbao pill could increase the heart rates of sinoatrial node damage model,and improve the sinus function. Conclusions Formaldehyde wet compressing method has more reabilites than formaldehyde drip method,and the percentage decreased in heart rate of damage degree should be controlled between 30% to 60% of basic heart rate,so that the duration of models are longer,and the death rates are lower.