Apelin对两肾一夹高血压大鼠离体主动脉环的舒张作用

目的：探讨小分子活性肽Apelin—13对两肾一夹（2K1C）高血压大鼠离体主动脉环的舒张作用及意义。方法：①清洁级雄性SD大鼠27只，随机分为正常对照组和2K1C高血压模型组。测定平均颈动脉压（mCAV）、左心重与体重比值（LVM／BW）以及右肾重／左肾重（RK／LK），以评价2K1C模型。②采用累计加药法，观察Apelin-13分别对用去甲肾上腺素（NE）预收缩的对照组大鼠和2K1C高血压组大鼠离体胸主动脉环张力的作用。结果：①模型组大鼠mCAP、LVM／BW和RK／LK分别较对照组高50．38％（P〈0．01）、32．16％（P〈0．01）和51．02％（P〈0．01）。②Apenn—13在（10^-11～10^-7）mol·L^-1浓度范围内对内皮完整的两组大鼠胸主动脉环具有浓度依赖性的舒张作用，且模型组舒张率高于对照组（P〈0．05），而模型组与对照．EC50相比差异无显著性（P〉0．05）。结论：Apelin-13具有显著的舒张主动脉的作用，并且对高血压大鼠血管环的舒张作用更强，提示Apelin—13在血管的保护作用中扮演了重要角色。

Effect of apelin-13 on vasodilatation of isolated thoracic aorta in rats of one-clip renal hypertension

Objective： To investigate the effect of apelin on vasodilatation of isolated thoracic aorta rings in rats of two Kindey one-clip renal hypertension and its significance. Methods： （1）Twentyseven male Sprague-Dawley （SD） rats with weight of 150 - 180 g were randomly divided into two groups, control rats（n=12） was estimated and model rats of two Kindey one-clip （2K1C） renal hypertension （n=15）. Then, the model of 2K1C renal hypertension by monitoring the mean carotid arterial pressure （mCAP）, measuring the ratio of left ventricular mass （left ventricle plus septum） to bodyweight （LVM/BW）, and right kidney to the left （RK/LK）. （2）Isolated aorta rings were perfused and were given the resting tension. Then, the effects of accumulated Apelin-13 on aorta rings with endothelium in pre-constricted with norepinephrine （NE） were observed. Results： （1）The mCAP and LVM/BW of 2K1C group were 50.38% and 32.16% higher than those of the control group, respectively （P〈0.01, P〈0.01）. And the ratio of RK/LK in the 2K1C group was 51.02% higher than that in the control group （P〈0.01）. （2）Apelin-18 was a potent vasodilatator on rat thoracic aorta. Apelin-13 at 10^-11- 10^-7 mol·L^-1 caused dose-depenent vasodilatation in endothelium intact rings pre-constricted with NE. Response of arteries from renal hypertension rats was increased （P 〈0.05）. But the values of EC50 were not significantly different （P〉0.05）. Conclusion： These results indicate that apelin-13 relaxes the thoracic aorta in the two groups and the response of vasodilatation is enhanced in the rat thoracic aortas from the 2KIC hypertension group. It may be an important protecting factor and play an important role in the protection of blood vessel.