Tozzi C A, Christiansen D L, Poiani G J, Riley D J
Department of Medicine, University of Medicine and Dentistry of New Jersey-Robert Wood Johnson Medical School, Piscataway 08854-5635.
Am J Respir Crit Care Med. 1994 May;149(5):1317-26. doi: 10.1164/ajrccm.149.5.8173773.
Increased vascular collagen content is a major feature of pulmonary vascular remodeling. The functional role of excess collagen in decreasing pulmonary vascular compliance has not been established. We determined whether there was a correlation between hydroxyproline content of rat pulmonary artery segments and elastance (EPA) of the pulmonary artery bed during development of hypoxic pulmonary hypertension (10% O2, 10 d) and normoxic recovery. EPA was measured by air-filled pressure-volume curves. After 10 d of hypoxia, hydroxyproline content increased approximately 2-fold in large segments (1,200-250 microns in diameter) but not significantly in small segments (> 250 microns). Elastance increased from 87 +/- 6 (SEM) to 145 +/- 8 mm Hg/ml (p < 0.05) within 5 d of hypoxia and returned to control value 3 wk after recovery. There was a correlation between collagen content and EPA in large segments during development of hypertension; no correlation was found during recovery from hypoxia. The ratio of hydroxyproline to total protein was unchanged in large segments after recovery from hypoxia but was increased in small segments after recovery. We conclude that increased collagen in large pulmonary arteries directly influences EPA during the development of hypoxic pulmonary hypertension.
血管胶原含量增加是肺血管重塑的一个主要特征。过量胶原在降低肺血管顺应性方面的功能作用尚未明确。我们确定了在低氧性肺动脉高压（10%氧气，10天）发展过程及常氧恢复期间，大鼠肺动脉段羟脯氨酸含量与肺动脉床弹性（EPA）之间是否存在相关性。通过充气压力-容积曲线测量EPA。低氧10天后，大段（直径1200 - 250微米）的羟脯氨酸含量增加约2倍，而小段（> 250微米）则无显著增加。低氧5天内，弹性从87 ± 6（SEM）增加至145 ± 8毫米汞柱/毫升（p < 0.05），恢复3周后恢复至对照值。在高血压发展过程中，大段胶原含量与EPA之间存在相关性；在低氧恢复过程中未发现相关性。低氧恢复后，大段羟脯氨酸与总蛋白的比值未改变，但小段恢复后增加。我们得出结论，在低氧性肺动脉高压发展过程中，大肺动脉中胶原增加直接影响EPA。
