CONTRACTILE PROPERTIES OF SMALL ARTERIAL RESISTANCE VESSELS IN SPONTANEOUSLY HYPERTENSIVE AND NORMOTENSIVE RATS
CONTRACTILE PROPERTIES OF SMALL ARTERIAL RESISTANCE VESSELS IN SPONTANEOUSLY HYPERTENSIVE AND NORMOTENSIVE RATS
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DOI：
10.1161/01.res.41.1.19
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发表时间：
1977-01-01
影响因子：
20.1
通讯作者：
HALPERN, W
中科院分区：
文献类型：
--
作者：
MULVANY, MJ;HALPERN, W
小动脉在原发性高血压外周阻力增加中起重要作用。直接测量5个月大鼠肠系膜床内两类小动脉阻力血管的固有力学和收缩特性。观察了老年正常血压Wistar-Kyoto大鼠（WKY）和自发性高血压大鼠（SHR）。当在100 mm Hg有效跨壁压下松弛时，血管具有246 μ m和153 μ m的平均内径。节段（1 mm）的安装方式应能够控制内周长并测量周向壁张力（T）。安装后，最大限度地激活每个血管（通过37 ° K+去极化）。C在5 mM Ca 2+存在下），其中Δ T近似最大，其中Δ T = Tactive-Treasured。根据测量的Δ T的平均值，估计（基于拉普拉斯方程）SHR血管将能够比WKY血管收缩34%的压力（P < 0.001）。这些血管的光学测量显示SHR血管的壁厚增加了23%（P < 0.02）。SHR和WKY血管的主动壁应力计算值无显著差异。在SHR血管中发现的更大的收缩性可能是由于它们具有更大的平滑肌细胞含量。检查了这些血管测量值以及大鼠的血压和心脏与体重比。比较点的可能性，导致高血压的心血管调节系统的干扰产生类似的细胞反应，在心肌和外周血管。
The small arteries play an important functional role in establishing the increased peripheral resistance found in essential hypertension. The direct measurement of the intrinsic mechanical and contractile properties of 2 categories of small arterial resistance vessels in the mesenteric bed of 5 mo. old normotensive Wistar-Kyoto rats (WKY) and spontaneously hypertensive rats (SHR) was investigated. The vessels had mean internal diameters of 246 .mu.m and 153 .mu.m when relaxed at 100 mm Hg effective transmural pressure. Segments (1 mm) were mounted in such a way that internal circumference could be controlled and the circumferential wall tension (T) measured. After mounting, each vessel was maximally activated (by K+ depolarization at 37.degree. C in the presence of 5 mM Ca2+) at an internal circumference for which .DELTA.T was approximately maximal, where .DELTA.T = Tactive - Trelaxed. From the average values of .DELTA.T measured it was estimated (on the basis of Laplace''s equation) that the SHR vessel would be able to contract against 34% greater pressures than the WKY vessels (P < 0.001). Optical measurements of the dimensions of these vessels showed a 23% greater wall thickness in the SHR vessels (P < 0.02). There were no significant differences in the calculated active wall stresses of the SHR and WKY vessels. The greater contractility found in the SHR vessels may be due to their having a greater smooth muscle cell content. These vessel measurements were examined as well as the rats'' blood pressures and heart to body weight ratios. The comparison points to the possibility that the disturbance to the cardiovascular regulatory system which results in hypertension produces similar cellular responses in both the myocardium and the peripheral vasculature.