氯沙坦对自发性高血压大鼠肾组织钙离子浓度的影响及与肾小动脉重建的关系研究

目的探讨钙超负荷与高血压。肾小动脉重建的关系及氯沙坦（Losartan）的治疗作用。方法正常血压Wistar-Kyoto（WKY）大鼠和同种的16周龄自发高血压大鼠（spontaneously hyperten—siverat，SHR）大鼠随机分为WKY对照组、SHR对照组、高剂量losartan组（SHR＋HL）、低剂量losar—tan组（SHR＋LL）。每组6只动物。给予正常饮食，饲养至24周。losartan溶于10ml生理盐水中灌胃，余组等量生理盐水灌胃。测量尾动脉血压、肾组织钙离子浓度、肾小动脉内羟脯氨酸含量并观察肾脏病理测量肾人球小动脉中膜厚度、血管内径及中膜厚度与内径比值（MT／LR）。结果SHR组肾组织钙离子浓度[（18．42±2．34）μ mol／g]、肾小动脉内羟脯氨酸含量[（8．26±2．02）mg／g]均大于WKY组[（11．83±1．98）μmoL／g，（5．16±0．98）mg／g]（t=3．116，3．258，P〈0．05），但两治疗组均有所降低，小于SHR组（t：2．946，P〈0．05）。SHR组肾内小动脉的壁厚[（5．25±1．13）μm]、壁厚内径比[（9．57±1．78）％]均大于WKY组相应比值[（4．03±0．16）斗m，（7．12±1．35）％]（t=2．836，3．425，P〈0．05），但两治疗组壁厚内径比[（7．64±1．29）％，（7．85±1．32）％]小于SHR组（t=3．512，3．648，P〈0．05）。结论losartan可以通过抑制细胞内钙超负荷、降低纤维化程度来改善肾小动脉的血管阻力，对高血压大鼠的。肾小动脉重建有逆转作用。

Effect of losartan on intracellular free calcium concentration and improved aortic elasticity in spontaneously hypertensive rat

Objective To investigate the effects of losartan on aortic elasticity and remodeling in spontaneously hypertensive rats (spontaneously hypertensive rats SHR). Methods WKY (Wistar - Kyoto ) rats with normal blood pressure and 16 weeks spontaneously hypertensive rats were randomly divided into WKY control group, SHR control group, high dose losartan group (SHR + HL), low doses losartan group (SHR + LL). Each group has six animals which were given normal diet for 24 weeks. Losartan which was dissolved in 10 ml physiological saline was filling in stomach, other groups were filling with physiological saline. Tail arterial blood pressure, kidney tissues calcium concentration, renal small artery hydroxyproline content was measured and small arteries wall thickness of Glomerularwas detected, and the ratio of thickness and inner diameter (MT/LR) in kidney pathological were observed. Results The calcium concentration of SHR group in kidney tissues was [(18.42±2.34)μmol/g], kidney small artery hydroxyproline content was [(8.26±2.02)mg/g], which were greater than WKY group [(11.83±1.98)μmol/g,(5.16±0.98)mg/g] (t＝3.116,3.258,P＜0.05), but the two treatment groups were less than SHR group (t＝2.946,P＜0.05), the difference was significant. Small arteries wall thickness of Glomerular was [(5.25±1.13)μm], the ratio of thickness and inner diameter (MT/LR) was [(9.57±1.78)%], which were greater than WKY group[(4.03±0.16)μm ,(7.12±1.35)%](t＝2.836,3.425,P＜0.05), but the wall thickness of two treatment groups were [(7.64±1.29)%,(7.85±1.32)%], the two treatment groups were less than SHR group (t＝3.512,3.648,P＜0.05). Conclusions Losartanmay inhibit intracellular calcium overload, reduce fibrosis degree and improve renal arteriole resistance and reverse the renal arteriole reconstruction of SHR rats.