Regulation of uveal and retinal blood flow in STZ-diabetic and non-diabetic rats; involvement of nitric oxide
Regulation of uveal and retinal blood flow in STZ-diabetic and non-diabetic rats; involvement of nitric oxide
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DOI：
10.1076/ceyr.19.4.330.5300
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发表时间：
1999-10-01
影响因子：
2
通讯作者：
Granstam, SO
中科院分区：
文献类型：
--
作者：
Granstam, E;Granstam, SO
目的.在实验性糖尿病和人类糖尿病中，已经发现血管内皮细胞功能受损的证据。本实验的目的是在实验性糖尿病的早期阶段测量葡萄膜和视网膜血流和血管阻力，并评估对照组和L-NAME-精氨酸组中乙酰胆碱和L-精氨酸的作用。方法采用放射性标记微球法对正常SD大鼠和STZ诱导的糖尿病大鼠进行实验研究。在本研究中，在正常和STZ糖尿病大鼠的葡萄膜中观察到相似的血流和血管阻力。基础血管舒张NO-张力的证据被发现在葡萄膜和两组的视网膜。在正常大鼠和糖尿病动物中，乙酰胆碱引起脉络膜血管舒张。正常大鼠的局部血流量从54 +/- 17增加到142 +/- 32 mg x min（-1），糖尿病大鼠的局部血流量从57 +/- 18增加到112 +/- 23 mg x min（-1）（分别为P < 0.05）。无血流动力学变化。在前葡萄膜中观察到，证明了这些血管床之间的反应性差异。在用NO合酶抑制剂L-NAME预处理的动物中，乙酰胆碱对脉络膜局部血流没有显著影响，表明NO是血管舒张的介质。结果表明，在大鼠实验性糖尿病的这一阶段，NO在眼血管床中的作用是正常的。
Purpose. In experimental and human diabetes mellitus evidence for an impaired function of the vascular endothelial cells has been found. The purpose of the present experiments was to measure uveal and retinal blood flow and vascular resistance at an early stage of experimental diabetes mellitus and to evaluate the effects of acetylcholine and L-arginine in control and L-NAME-pretreated animals.Methods The radioactively labelled microsphere method was applied to normal Sprague-Dawley rats and rats with STZ-induced diabetes of three weeks duration.Results. In the present study, similar blood flow and vascular resistance were observed in the uvea of normal and STZ-diabetic rats. Evidence for a basal vasodilating NO-tone was found both in the uvea and in the retina of both groups. In the normal rats as well as in the diabetic animals, acetylcholine induced choroidal vasodilation. Local blood flow increased from 54 +/- 17 to 142 +/- 32 mg x min(-1) in normal rats and from 57 +/- 18 to 112 +/- 23 mg x min(-1) in diabetic rats (P < 0.05 respectively). No hemodynamic changes were. observed in the anterior uvea, demonstrating a difference in reactivity between these vascular beds. Tn animals pretreated with the NO-synthase inhibitor L-NAME, acetylcholine did not significantly affect local blood flow in the choroid, suggesting NO as a mediator of the vasodilation.Conclusion. The results indicate a normal action of NO in the ocular vascular beds at this stage of experimental diabetes mellitus in the rat.