Vassallo D V, Vasquez E C, Cabral A M, Mill J G
Departamento de Ciências Fisiológicas, Universidade Federal de Espírito Santo, Vitória, Brasil.
Braz J Med Biol Res. 1988;21(3):625-8.
The effects of acute sinoaortic baroreceptor denervation were studied in left ventricle papillary muscles obtained from rats after 3 days of sinoaortic denervation (SAD) and compared to sham-operated controls (SO). SAD and SO muscles developed similar force (F) and rate of force development (dF/dt). To test changes in beta-adrenoceptor sensitivity, isoproterenol (IPA) was used in four doses (0.1, 0.2, 0.4 and 0.8 micrograms/ml). F increased as expected, the increments tended to be larger in the SAD muscles although they were not statistically significant. dF/dt behaved in a similar way, but the increments produced by IPA were significantly larger for SAD muscles. The inotropic effects produced by pauses of increasing duration (5, 15 and 30 s) were also studied but in this case both the changes of F and dF/dt were similar. These results clearly show that there is a selective increase in beta-adrenoceptor sensitivity resulting from acute sinoaortic baroreceptor denervation.
研究了急性窦主动脉压力感受器去神经支配对窦主动脉去神经支配（SAD）3天后大鼠左心室乳头肌的影响，并与假手术对照组（SO）进行比较。SAD组和SO组的肌肉产生的力量（F）和力量发展速率（dF/dt）相似。为了测试β-肾上腺素能受体敏感性的变化，使用了四种剂量（0.1、0.2、0.4和0.8微克/毫升）的异丙肾上腺素（IPA）。F如预期增加，SAD组肌肉的增量往往更大，尽管无统计学意义。dF/dt表现类似，但IPA对SAD组肌肉产生的增量显著更大。还研究了不同时长（5、15和30秒）间歇产生的变力作用，但在这种情况下，F和dF/dt的变化相似。这些结果清楚地表明，急性窦主动脉压力感受器去神经支配会导致β-肾上腺素能受体敏感性选择性增加。
