β3肾上腺素能受体阻滞剂SR59230A对心力衰竭大鼠心功能及β3肾上腺素能受体表达的影响

目的：评价β3肾上腺素能受体（β3-AR）阻滞剂SR59230A（SR）对心力衰竭大鼠心功能及β3-AR表达的影响。方法：♂Wistar大鼠85只，取8只设立对照组，其余77只应用异丙基肾上腺素成功建立20只心力衰竭模型后随机分为安慰剂组和SR组，并分别腹腔注射生理盐水和SR，7周后检测超声心动图、血流动力学各指标及β3-AR蛋白表达水平。结果：与安慰剂组比较，SR组短轴缩短率、射血分数、左室收缩末压、左室压力最大上升及下降速率明显增加（P〈0．01或P〈0．05），而心率、左室舒张末压及β3-AR蛋白表达水平显著降低（P〈0．05或P〈0．01）。结论：β3-AR阻滞剂SR能够改善心力衰竭大鼠心功能，该作用可能与其直接阻滞并下调β3-AR表达有关。

Effect of SR59230A as a β3 Adenoreceptor on Cardiac Function and β3- AR Expression in Rats with Heart Failure

OBJECTIVE： To evaluate the effect of β3 Adrenoceptor （β3-AR） antagonist SR59230A（SR） on cardiac function and expression of β3-AR in rats with heart failure. METHODS： A total of 85 male Wistar rats were enrolled： 8 were assigned to control group, and 77 were established into heart failure model and then 20 rats that modelled successly assigned randornly to placebo group or SR group, with placebo group intraperitoneally injected with normal saline and SR group with SR. The echocardiogram, hemodynamics, and expression of β3-AR in rats after 7-week treatment were followed. RESULTS： In SR group compared with placebo group, shortening fraction, ejection fraction, left ventricular end systolic pressure, dp/dtmax. and dp/dmin, were significantly higher （P〈0.01 or P〈0.05）, while heart rate and left ventricular end diastolic pressure, and the expression of β3 - AR were significantly lower （ P 〈 0.05 or P 〈0.01）. CONCLUSION ： β3 - AR antagonist SR can improve cardiac function in rats with heart failure and this action may relate to its direct blocking and downregulation of β3-AR.