中文摘要：

为探讨钙拮抗剂硝苯地平对低温诱发的肉鸡肺血管重塑的影响,动态观察肺小动脉血管中膜平滑肌增殖及管腔面积的改变。150只AA商品代肉仔鸡常规育雏,15日龄随机分为3组：常温（22-24℃）对照组、低温（9-11℃）组、低温（9-11℃）硝苯地平组。分别于低温处理后2周（28日龄）、3周（36日龄）、4周（44日龄）随机各抽取10只测定肺动脉压（PAP）,同时取肺组织做石蜡切片,以Weigert弹力纤维染色,图像分析测定肺小动脉外径和内径、管腔面积和管总面积,计算相对中膜厚度（mMTPA）及管壁面积/管总面积（WA/TA）。结果表明：（1）硝苯地平抑制了低温诱发的肉鸡肺动脉压的升高,28日龄、36日龄和44日龄,硝苯地平组mPAP显著低于低温组（P〈0.05）;（2）硝苯地平能抑制肺小动脉中膜平滑肌增生,表现在28日龄、36日龄和44日龄时,硝苯地平组50-100μm的肺小动脉mMTPA显著低于低温组（P〈0.05）,100-200μm肺小动脉的组间差异与此类似;（3）硝苯地平抑制肺小动脉血管壁的增厚,3个日龄的硝苯地平组肺小动脉WA/TA显著低于低温组（P〈0.05）。可见,硝苯地平抑制低温诱发的肉鸡肺动脉高压和肺血管重塑。

英文摘要：

To investigate the effect of nifidepine,a calcium antagonist,on pulmonary vascular remodeling induced by low ambient temperature,the dynamic changes of pulmonary arterioles medial thickness and pulmonary blood vessel endometry area caused by proliferous smooth muscle cells in broiler chickens were observed.One hundred and fifty 15-day old commercial broiler chickens were randomly divided into three groups as follows：50birds were exposed to normal temperature（22-24 ℃）,50 birds were exposed to low temperature（9-11℃）,and 50 birds were exposed to low temperature（9-11 ℃）.At 28,36 and 44days of age,10 birds were randomly sampled from each group.Pulmonary arterial pressure（PAP）was determined as index of pulmonary hypertension.The measurement ofmean medial thickness in pulmonary arterioles（mMTPA）and ratio of vessel wall area to vessel total area（WA/TA）were accomplished by using the microscopic image analysis program.The results showed as follows：（1）nifidepine significantly inhibited the increase of mPAP（kPa）,Nifidepine group was lower than low temperature group at 28,36 and 44days（P〈0.05）;（2）nifidepine could inhibit the medial smooth muscular prolieration of pulmonary arterioles,the mMTPA of 50-100μm pulmonary arterioles of low temperature group was obviously higher than that of nifidepine group（P〈0.05）at 28,36 and 44days of age.The differences between groups in 100-200μm of pulmonary arterioles had similar trend;（3）the WA/TA of pulmonary arterioles of low temperature group was obviously higher than that of nifidepine group（P〈0.05）,nifidepine inhibited the hypertrophy of the vessel wall.In summary,the data indicated that nifidepine could inhibit pulmonary hypertension and pulmonary vascular remodeling induced by low ambient temperature in broiler chickens.