Lundin S, Ricksten S E, Thorén P
J Hypertens Suppl. 1983 Dec;1(2):68-70.
Spontaneously hypertensive (SHR) and Wistar-Kyoto rats (WKY) were compared with regard to the interaction between cortico-hypothalamic alerting responses and the baroreflex influences on neurogenic cardiovascular control. Baroreceptor sensitivity was assessed as heart rate (HR) and renal sympathetic nerve activity (RSNA) reduction per mmHg mean arterial pressure (MAP) increase by phenylephrine infusion. Response to 'mental stress' was studied. Addition of 'mental stress' during baroreceptor activation (30 mmHg MAP increase) was also performed. RSNA was higher in SHR than in WKY during rest and increased more during stress. Baroreflex sensitivity was reduced in SHR compared with WKY concerning HR (0.44 +/- 0.06 versus 0.78 +/- 0.08%/mmHg). Percentage RSNA reduction was similar, while RSNA reduction appeared greater in SHR in comparison with WKY (0.10 +/- 0.02 and 0.06 +/- 0.01 microV/mmHg, P less than 0.12). During baroreflex activation 'mental stress' increased both HR (+24 +/- 7%) and RSNA (+114 +/- 21%) in SHR with almost no changes in WKY. The results suggest an increased cortico-hypothalamic activity in SHR, which is clearly augmented during 'mental stress' and readily overcomes baroreflex inhibitory influences on sympathetic activity.
对自发性高血压大鼠（SHR）和Wistar - Kyoto大鼠（WKY）在皮质 - 下丘脑警觉反应与压力反射对神经源性心血管控制的影响之间的相互作用方面进行了比较。通过静脉注射去氧肾上腺素使平均动脉压（MAP）每升高1 mmHg来评估压力感受器敏感性，以心率（HR）和肾交感神经活动（RSNA）的降低作为指标。研究了对“精神应激”的反应。在压力感受器激活期间（MAP升高30 mmHg）也加入了“精神应激”。休息时SHR的RSNA高于WKY，应激期间增加得更多。与WKY相比，SHR的压力反射敏感性在HR方面降低（0.44±0.06对0.78±0.08%/mmHg）。RSNA降低的百分比相似，但与WKY相比，SHR的RSNA降低似乎更大（0.10±0.02和0.06±0.01 μV/mmHg，P＜0.12）。在压力反射激活期间，“精神应激”使SHR的HR（+24±7%）和RSNA（+114±21%）均增加，而WKY几乎没有变化。结果表明SHR中皮质 - 下丘脑活动增加，在“精神应激”期间明显增强，并容易克服压力反射对交感神经活动的抑制作用。
