Effects of hindlimb unloading on rat cerebral, splenic, and mesenteric resistance artery morphology
Effects of hindlimb unloading on rat cerebral, splenic, and mesenteric resistance artery morphology
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DOI：
10.1152/jappl.1999.87.6.2115
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发表时间：
1999-12-01
影响因子：
3.3
通讯作者：
Delp, MD
中科院分区：
文献类型：
--
作者：
Wilkerson, MK;Muller-Delp, J;Delp, MD
大鼠后肢卸载（HU）会引起体液向头侧移动。我们假设，假定的颅内液体压力增加和周围液体压力减少会改变 2 周 HU 雄性 Sprague-Dawley 大鼠的阻力动脉形态。为了检验这一假设，从对照 (C) 和 HU 动物中取出脑基底动脉、肠系膜动脉和脾动脉。对血管进行插管，并将管腔压力设置为 60 cmH(2)O。然后用10(-4)M硝普钠松弛阻力动脉，固定，并切成横截面(5μm厚)。测定中膜横截面积 (CSA)、腔内 CSA、中膜层厚度、血管外周长和中膜核数。在基底动脉中，中层CSA（HU 17,893 +/- 2,539 μm(2)；C 12,904 +/- 1,433 μm(2)）和厚度（HU 33.9 +/- 4.1 μm；C 22.3 +/- 3.2 μm）均随着后肢卸载而增加（P < 0.05），腔内CSA减少（HU 33.9 +/- 4.1 μm；C 22.3 +/- 3.2 μm）。 7,816 +/- 3,045 μ m(2)；C 13,469 +/- 5,500 μ m(2)) (P < 0.05)，血管外周长和中膜核数未改变。 HU和C大鼠的肠系膜或脾阻力动脉形态没有差异。这些发现表明，后肢卸载引起的头动脉压力增加，相应地，周壁应力增加导致基底动脉平滑肌细胞肥大。
Hindlimb unloading (HU) of rats induces a cephalic shift in body fluids. We hypothesized that the putative increase in cranial fluid pressure and decrease in peripheral fluid pressure would alter the morphology of resistance arteries from 2-wk HU male Sprague-Dawley rats. To test this hypothesis, the cerebral basilar, mesenteric, and splenic arteries were removed from control (C) and HU animals. The vessels were cannulated, and luminal pressure was set to 60 cmH(2)O. The resistance arteries were then relaxed with 10(-4) M nitroprusside, fixed, and cut into transverse cross sections (5 mu m thick). Media cross-sectional area (CSA), intraluminal CSA, media layer thickness, vessel outer perimeter, and media nuclei number were determined. In the basilar artery, both media CSA (HU 17,893 +/- 2,539 mu m(2); C 12,904 +/- 1,433 mu m(2)) and thickness (HU 33.9 +/- 4.1 mu m; C 22.3 +/- 3.2 mu m) were increased with hindlimb unloading (P < 0.05), intraluminal CSA decreased (HU 7,816 +/- 3,045 mu m(2); C 13,469 +/- 5,500 mu m(2)) (P < 0.05), and vessel outer perimeter and media nuclei number were unaltered. There were no differences in mesenteric or splenic resistance artery morphology between HU and C rats. These findings suggest that hindlimb unloading-induced increases in cephalic arterial pressure and, correspondingly, increases in circumferential wall stress result in the hypertrophy of basilar artery smooth muscle cells.