Kunze D L
Am J Physiol. 1986 May;250(5 Pt 2):H866-70. doi: 10.1152/ajpheart.1986.250.5.H866.
Electrical stimulation of the aortic nerve of the anesthetized rabbit was used to determine whether there is a central nervous system component to acute resetting of the baroreceptor reflex. After stimulation of the aortic nerve for 5 min at 10 Hz, a ramp test stimulus to the nerve produced a reflex arterial pressure response that was attenuated as compared with that produced by the same ramp prior to the five-min stimulation period. Renal sympathetic nerve activity was recorded simultaneously to determine whether a reduction in the magnitude of the reflex inhibition of sympathetic activity produced by the depressor nerve stimulation could account for the attenuated arterial pressure response. Renal activity during the test ramp was reduced to the same value both before and after the constant stimulus period and thus did not correlate with the attenuated pressure response. There was, however, prolonged inhibition of tonic sympathetic activity after the 5-min stimulus period such that during the test stimulus there was less sympathetic activity to inhibit. The results were similar when sympathetic activity was recorded from branches of the sciatic nerve and from thoracic postganglionic nerves. In these nerves the period of prolonged inhibition after aortic nerve stimulation was up to 5 min. The attenuated pressure response to baroreceptor nerve stimulation after a constant stimulus appears to reflect the reduced change in sympathetic activity rather than the value to which the sympathetic activity falls.
对麻醉兔的主动脉神经进行电刺激，以确定压力感受器反射的急性重置是否存在中枢神经系统成分。以10Hz的频率对主动脉神经刺激5分钟后，对该神经施加斜坡测试刺激所产生的反射性动脉压反应，与在5分钟刺激期之前由相同斜坡产生的反应相比有所减弱。同时记录肾交感神经活动，以确定减压神经刺激所产生的交感神经活动反射性抑制幅度的降低是否可以解释动脉压反应的减弱。在测试斜坡期间，恒定刺激期前后的肾活动均降至相同值，因此与减弱的压力反应无关。然而，在5分钟刺激期后，紧张性交感神经活动受到长时间抑制，使得在测试刺激期间可被抑制的交感神经活动减少。当从坐骨神经分支和胸神经节后神经记录交感神经活动时，结果相似。在这些神经中，主动脉神经刺激后的长时间抑制期长达5分钟。在恒定刺激后，对压力感受器神经刺激的压力反应减弱似乎反映了交感神经活动变化的减少，而不是交感神经活动下降到的值。
