Judy W V, Farrell S K
Hypertension. 1979 Nov-Dec;1(6):605-14. doi: 10.1161/01.hyp.1.6.605.
The combined and individual carotid sinus and aortic baroreceptor control of sympathetic nerve activity (SNA) and mean arterial pressure (MAP) were studied by direct measurement in groups of spontaneously hypertensive rats (SHR) and normotensive Kyoto Wistar rats (WKY) of 5 to 40 weeks of age. The SHR showed a significantly greater SNA and resultant MAP increase as a function of age compared to that of the WKY rats. Both SHR and WKY rats showed a significant rise in SNA and MAP with ablation of all four major baroreceptors. The proportionate change of SNA and MAP after ablation was greater in the younger SHR than in the younger WKY groups and the change in these decreased as a function of age in the SHR. The reflex inhibition of SNA via baroreceptor stimulation also decreased as a function of age in the SHR, due to a 43% loss of aortic inhibitory function; no significant loss of carotid sinus function was found in either the SHR or WKY. The decrement in aortic function occurred after the rapid phase of blood pressure development; therefore baroreceptor dysfunction cannot be the cause of the high SNA and MAP observed in young SHR. An upward resetting of central sympathetic centers was evaluated via the baroreceptor deafferentation; and it appears that the hyperactive sympathetic nervous system and resultant hypertension in the SHR is due to central resetting of sympathetic centers rather than baroreceptor dysfunction.
通过直接测量5至40周龄的自发性高血压大鼠（SHR）和正常血压的京都Wistar大鼠（WKY）组，研究了颈动脉窦和主动脉压力感受器对交感神经活动（SNA）和平均动脉压（MAP）的联合及单独控制。与WKY大鼠相比，SHR随着年龄增长，SNA显著增加，MAP也相应升高。在切除所有四个主要压力感受器后，SHR和WKY大鼠的SNA和MAP均显著升高。切除后，年轻SHR组的SNA和MAP的比例变化大于年轻WKY组，且在SHR中，这些变化随年龄增长而减小。由于主动脉抑制功能丧失43%，SHR中通过压力感受器刺激对SNA的反射性抑制也随年龄增长而降低；在SHR或WKY中均未发现颈动脉窦功能有明显丧失。主动脉功能的减退发生在血压快速上升阶段之后；因此，压力感受器功能障碍不可能是年轻SHR中高SNA和MAP的原因。通过压力感受器去传入评估中枢交感神经中枢的向上重置；似乎SHR中交感神经系统过度活跃及由此导致的高血压是由于交感神经中枢的中枢重置，而非压力感受器功能障碍。
