Baroreflex control of sympathetic nerve activity after elevations of pressure in conscious rabbits.
Baroreflex control of sympathetic nerve activity after elevations of pressure in conscious rabbits.
复制标题
清醒兔子压力升高后压力反射对交感神经活动的控制。
DOI：
10.1152/ajpheart.1985.248.6.h827
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发表时间：
1985
期刊：
影响因子：
--
通讯作者：
Bishop,VS
中科院分区：
文献类型：
--
作者：
Undesser,KP;Pan,JY;Lynn,MP;Bishop,VS
本研究的目的是评估快速压力感受器重置对清醒家兔肾交感神经活动的压力反射控制的影响。记录肾交感神经活动，并将其作为压力反射传出肢体的指标。同时记录心率和动脉压。用苯肾上腺素或血管紧张素II将动脉压升高到消除肾交感神经活动的水平，并在此水平上维持1至60分钟。当压力恢复到控制水平时，肾交感神经活动被抑制长达90分钟，抑制的持续时间取决于压力刺激的大小和持续时间。在抑制神经活动的这段时间，产生了压力反射曲线。与对照气压反射曲线相比，此时产生的曲线也受到抑制。随着时间的推移，被抑制的气压反射曲线恢复到控制状态。进一步的研究表明，肾交感神经活动的抑制是通过压力刺激期间压力感受器传入活动的持续增加介导的，而不是由于苯肾上腺素的中枢作用。这项研究表明，尽管压力感受器传入活动可能会迅速重置，但肾交感神经活动似乎不会像预期的那样增强。
The purpose of this study was to assess the effect of rapid baroreceptor resetting on the baroreflex control of renal sympathetic nerve activity in conscious rabbits. Renal sympathetic nerve activity was recorded and used as an index of the efferent limb of the baroreflex. Heart rate and arterial pressure were also recorded. Arterial pressure was raised with either phenylephrine or angiotensin II to a level that eliminated renal sympathetic nerve activity and was maintained at this level for periods of time ranging from 1 to 60 min. On returning pressure to control levels, renal sympathetic nerve activity remained suppressed for up to 90 min, with the duration of the suppression dependent on the magnitude and duration of the pressure stimulus. During this period of suppressed nerve activity, baroreflex curves were generated. The curves produced at this time were also suppressed as compared with control baroreflex curves. With time, the suppressed baroreflex curves returned to control. Further studies were performed to show that the suppression of renal sympathetic nerve activity was mediated via the prolonged increase in baroreceptor afferent activity during the pressure stimulus and was not due to a central effect of phenylephrine. This study indicates that although baroreceptor afferent activity may reset rapidly, there does not appear to be an augmentation of renal sympathetic nerve activity as would be expected.