Batra S, Rakusan K, Campbell S E
Department of Physiology, Faculty of Medicine, University of Ottawa, Ontario, Canada.
Microvasc Res. 1991 Jan;41(1):29-40. doi: 10.1016/0026-2862(91)90005-v.
Capillary geometry was examined in normal and hypertrophic myocardium. Hypertrophy was induced by aortic constriction in neonatal rats. Morphometric data were obtained from tissue sections exposed to a staining technique that distinguished the arteriolar and venular portions of capillaries by color. In sham-operated controls, the theoretical tissue region supplied by a single capillary decreased from the arteriolar to venular side (499 +/- 3 microns 2 and 456 +/- 5 microns 2, P less than 0.05; mean +/- SE) of capillaries. In hypertrophy, only arteriolar capillary tissue regions increased in size, thus enlarging the difference between arteriolar and venular ends (547 +/- 6 microns 2 and 464 +/- 5 microns 2, P less than 0.01). Intercapillary distances, measured at various levels along the capillary path length, decreased in a stepwise manner in both normal and hypertrophic hearts. In hypertrophic hearts, mean capillary path length was significantly longer than in controls, but the total length of the individual capillary nets was reduced. In both groups, arteriolar capillary segment length was longer (P less than 0.01) than venular capillary segment length. Given that PO2 values are lower on the venular side of capillaries, this spatially distinctive geometry in normal myocardium: smaller domains, shorter intercapillary distances and segment lengths, would provide favorable geometric conditions for oxygen diffusion. In hypertrophy, average intercapillary distance increased, and the distinction between arteriolar and venular portions of capillaries was further exacerbated.
研究了正常心肌和肥厚心肌中的毛细血管几何形态。通过对新生大鼠进行主动脉缩窄诱导心肌肥厚。从经染色技术处理的组织切片中获取形态学数据，该染色技术可通过颜色区分毛细血管的小动脉部分和小静脉部分。在假手术对照组中，由单个毛细血管供应的理论组织区域从毛细血管的小动脉侧到小静脉侧减小（分别为499±3平方微米和456±5平方微米，P<0.05；均值±标准误）。在心肌肥厚时，只有小动脉毛细血管组织区域增大，从而扩大了小动脉端和小静脉端之间的差异（分别为547±6平方微米和464±5平方微米，P<0.01）。在正常心脏和肥厚心脏中，沿着毛细血管路径长度在不同水平测量的毛细血管间距均呈逐步减小。在肥厚心脏中，平均毛细血管路径长度显著长于对照组，但单个毛细血管网的总长度缩短。在两组中，小动脉毛细血管段长度均长于（P<0.01）小静脉毛细血管段长度。鉴于毛细血管小静脉侧的PO2值较低，正常心肌中这种空间上独特的几何形态：较小的区域、较短的毛细血管间距和段长度，将为氧气扩散提供有利的几何条件。在心肌肥厚时，平均毛细血管间距增加，并且毛细血管小动脉部分和小静脉部分之间的差异进一步加剧。
