颈动脉窦电刺激对野百合碱诱导肺动脉高压大鼠的影响

Effect of Carotid Baroreceptor Stimulation in Monocrotaline-induced Pulmonary Hypertension in Rats

目的探索在野百合碱(monocrotaline,MCT)诱导的肺动脉高压(pulmonary arterial hypertension,PAH)大鼠模型中,通过心脏超声检测评价颈动脉窦压力感受器电刺激(carotid baroreceptor stimulation,CBS)对PAH大鼠右心室功能的影响。方法将16只健康雄性SD大鼠随机分为4组,即Con-sham组、Con-CBS组、PAH-sham组和PAH-CBS组。Con-sham组和Con-CBS组一次性腹腔注射0.9%NaCl注射液,PAH-sham组和PAH-CBS组一次性腹腔注射MCT,MCT注射4周后通过超声仪器测量各组大鼠的肺动脉加速时间(pulmonary acceleration time,PAT)、射血时间(ejection time,ET)、右心室舒张末期厚度(right ventricular end-diastolic thickness,RVEDT)、右心室舒张末期前后径(right ventricular anteroposterior diameter in diastolic,RVAPDd)、右心室流出道内径(right ventricular outflow tract diameter,RVOTD)、右心室面积变化率(right ventricular fractional area change,RVFAC),同时测量左心室射血分数(left ventricular ejection fraction,LVEF)及左心室短轴缩短率(left ventricular fractional shortening,LVFS)。结果MCT注射4周后,PAH-sham组大鼠出现呼吸加快,脚趾发绀;与Con-sham组比较,超声提示PAH-sham组PAT明显变短,表明肺动脉高压大鼠造模成功。同时,超声还提示RVEDT、RVAPDd及RVOTD明显增加,RVFAC明显减低,给予CBS刺激后,可以改善上述指标的恶化。结论CBS可以改善MCT诱导的PAH大鼠的右心室功能。

Objective To investigate the effect of Carotid Baroreceptor Stimulation(CBS)on right ventricular function in monocrotaline-induced pulmonary arterial hypertension in rats by echocardiographic parameters.Methods Sixteen healthy male Sprague Dawley(SD)rats were randomly divided into 4 groups:Con-sham group,Con-CBS group,PAH-sham group and PAH-CBS group.Con-sham group and Con-CBS group were intraperitoneally injected with normal saline,monocrotaline(MCT)was intraperitoneally injected in the MCT-sham group and MCT-CBS group.Four weeks after MCT injection,pulmonary acceleration time(PAT),ejection time(ET),right ventricular end-diastolic thickness(RVEDT),right ventricular anteroposterior diameter in diastolic(RVAPDd),right ventricular outflow tract diameter(RVOTD),and right ventricular fractional area change(RVFAC)were measured by small animal ultrasound instrument under isoflurane anesthesia.Moreover,we measured left ventricular ejection fraction(LVEF)and left ventricular fractional shortening(LVFS)to assess left ventricular function.Results Four weeks after MCT injection,compared with the Con-sham group,ultrasound indicated that PAT was significantly decreased in the PAH-sham group,indicating that the model of the rats with pulmonary hypertension was successful.At the same time,ultrasound also indicated that RVEDT,RVAPDd and RVOTD also increased significantly,and RVFAC decreased significantly.However,these parameters could be improved by CBS.Conclusion CBS can improve right ventricular function in monocrotaline-induced pulmonary arterial hypertensive rats.