慢性缺氧时肺腺泡内动脉结构变化与血流动力学变化的关系

在用低压舱模拟连续低压缺氧不同时间的大鼠模型上,观察分析了肺腺泡内动脉结构重建变化与肺循环血流动力学变化的关系。结果表明:缺氧早期(24h后),肺腺泡内动脉即有明显肌化(肌性动脉段增多,非肌性动脉段减少)。随缺氧时间延长,肺腺泡内动脉肌化与肺动脉压增高及右心室代偿性肥厚密切相关。构成肺腺泡内动脉的三种血管段随缺氧时间延长有不同变化趋势,反映出缺氧早期肌性动脉段增多主要经原有部分肌性动脉段转变为肌性动脉段的短捷途径;以后非肌性动脉段经部分肌性动脉段转变为肌性动脉段逐渐成为主要途径。

Relationship between Changes of Intra-acinar Arteries Structural and Hemodynamics during Chronic Hypoxia

Male Wistar rats were placed in a hypobaric chamber (5000m) for 1, 3, 5, 7, 14, 21, and 40d. After 24h of exposure, the significant muscularization of pulmonary arterioles was found. Such structural remodeling of IAA might increase the resistance of the pulmonary arterial bed and therefore contribute to the occurrence of pulmonary hypertension. Along with the prolongation of hypoxic exposure, mPAP and RVSP continually rouse and LV+S/RV continually dropped, 0<50nm TWPV% was closely conelated with mPAP and RVSP as well as LV + S/RV, suggesting muscularity of IAA might play an important role in the development of pulmonary hypertension. Furthermore, the different changing tendencies of MA%, PMA%, and NMV% in the course of exposure indicated that the process of muscularization of IAA might develop mainly from PMA in the early stage, and later from both NMA nd PMA.