Fath S W, Burkhart H M, Miller S C, Dalsing M C, Unthank J L
Department of Surgery, Indiana University Medical Center, Indianapolis, Ind., USA.
J Vasc Res. 1998 Jul-Aug;35(4):257-64. doi: 10.1159/000025592.
Previous studies have demonstrated endothelial and smooth muscle hyperplasia occur during arterial luminal expansion associated with elevation of arterial wall shear rates. The current study investigated whether remodeling induced by elevated wall shear would ultimately result in a vessel with intimal and medial cell densities and other wall characteristics similar to control arteries. A rat mesenteric model was used in which collateral wall shear is restored to normal 4 weeks after arterial occlusion. Twelve weeks after shear elevation, paired in vivo measurements indicated that the maximum collateral inner diameter was increased 27-75%. Morphometric evaluation of collateral cross sections indicated that, relative to control arteries, luminal and medial areas were increased 79 +/- 22 and 56 +/- 15%. Collateral medial cell density was decreased (1.12 +/- 0.044 vs. 1.35 +/- 0.005 nuclei/1,000 micrometer(2) but intimal cell density was similar (2.86 +/- 0.166 vs. 2.49 +/- 0.102 nuclei/100 micrometer luminal perimeter). Medial thickness to radius ratio was also similar between control and collateral arteries. Thus, for the wall characteristics evaluated, there are many similarities between enlarged collaterals and control arteries. Comparison of nuclear numbers in arterial cross sections of the current and previous studies suggest that intimal and medial cellular regression is correlated with a decrease in wall shear force toward normal levels.
先前的研究表明，在动脉腔扩张过程中，随着动脉壁剪切率升高，会出现内皮和平滑肌增生。本研究调查了壁剪切力升高所诱导的重塑是否最终会导致血管的内膜和中膜细胞密度以及其他壁特征与对照动脉相似。使用大鼠肠系膜模型，其中在动脉闭塞4周后，侧支壁剪切力恢复正常。在剪切力升高12周后，配对的体内测量表明，侧支最大内径增加了27%-75%。侧支横截面的形态计量学评估表明，相对于对照动脉，管腔和中膜面积分别增加了79±22%和56±15%。侧支中膜细胞密度降低（1.12±0.044对1.35±0.005个细胞核/1000微米²），但内膜细胞密度相似（2.86±0.166对2.49±0.102个细胞核/100微米管腔周长）。对照动脉和侧支动脉之间的中膜厚度与半径比也相似。因此，就所评估的壁特征而言，扩大的侧支与对照动脉之间存在许多相似之处。对本研究和先前研究的动脉横截面细胞核数量进行比较表明，内膜和中膜细胞消退与壁剪切力向正常水平降低相关。
