美托洛尔降压效果与自发性高血压大鼠心肌β1肾上腺素能受体表达差异的相关性

Relationship between the antihypertensive effect of metoprolol and myocardial β1-adrenergic receptor expression in spontaneous hypertension rats

目的研究心肌β1肾上腺素能受体(β1-AR)表达差异对自发性高血压大鼠(SHR)美托洛尔降压疗效的影响。方法按照体重将SHR随机分为2组:SHR空白对照组和SHR实验组,每组6只;按照体重将基因敲除自发性高血压大鼠(GK-SHR)随机分为2组:GK-SHR空白对照组和GK-SHR实验组,每组6只。实验组大鼠每次灌胃10 m L·kg^-1美托洛尔悬浮液,空白对照组大鼠每次灌胃10 mL·kg^-10. 9%NaCl,连续4周。用无创血压计每周监测大鼠血压的变化。结果4周末,SHR空白对照组、SHR实验组的收缩压分别为(202. 51±6. 76),(173. 62±2. 39) mmHg;上述这2组的舒张压分别为(150. 90±4. 26),(128. 60±2. 77) mm Hg;SHR实验组的收缩压和舒张压均显著低于SHR空白对照组,差异均有统计学意义(均P <0. 05)。GK-SHR空白对照组和GK-SHR实验组的收缩压分别为(180. 27±2. 70),(179. 82±2. 51)mmHg;上述这2组的舒张压分别为(132. 27±4. 90),(132. 39±5. 28) mmHg;GK-SHR实验组与GK-SHR空白对照组的收缩压和舒张压相比,差异均无统计学意义(均P> 0. 05)。结论美托洛尔降压疗效与SHR心肌β1-AR表达差异有关,SHR心肌β1-AR表达下调可以影响美托洛尔的疗效。

Objective To investigate the effect of myocardial β1 - adrenergic receptor(β1 - AR) expression on the hypotension effect of metoprolol in spontaneous hypertension rats ( SHR). Methods SHR were divided into two groups according to weight randomly: SHR blank control group and SHR experimental group;Gene knockout spontaneously hypertensive rats ( GK - SHR) were also randomly divided into two groups: GK - SHR blank control group and GK - SHR experimental group,6 rats in each group. Experimental group were given 10 mL·kg^- 1 submetoprolol suspension each time,and blank control group were given 10 mL·kg^- 1 physiological saline each time for four consecutive weeks. The blood pressure changes of all rats were monitored weekly with nonin-vasive sphygmomanometers. Results After four - weeks,the systolic blood pressure in SHR blank control group and SHR experimental group were ( 202. 51 ± 6. 76),( 173. 62 ± 2. 39) mmHg;the diastolic blood pressure in the above two groups were ( 150. 90 ± 4. 26),( 128. 60 ± 2. 77) mmHg,respectively;the systolic and diastolicblood pressure of SHR experimental group were significantly lower than those of SHR blank control group with statistically significant ( all P < 0. 05). The systolic blood pressure in GK - SHR blank control group and GK - SHR experimental group were ( 180. 27 ± 2. 70),( 179. 82 ± 2. 51) mmHg;the diastolic blood pressure in the two groups were ( 132. 27 ± 4. 90),( 132. 39 ± 5. 28) mmHg;there was no significant difference in systolic and diastolic blood pressure between GK - SHR group and GK - SHR control group ( all P > 0. 05). Conclusion The antihypertensive effect of metoprolol was related to myocardial β1 - AR expression of spontaneously hypertensive rats,the low - expression of myocardial β1 - AR of SHR may affect the effect of metoprolol.