Muratani H, Takishita S, Kawazoe N, Tozawa M, Fukiyama K
Third Department of Internal Medicine, School of Medicine, University of The Ryukyus, Okinawa, Japan.
Blood Press Suppl. 1992;3:60-7.
An enhanced renal vasoconstrictive response to emotional stress may be related to the pathogenesis of essential hypertension. We examined the effects of chronic manidipine treatment on renal blood flow (RBF) responses to air jet stress, angiotensin II (ANG II), and endothelin-3 (ET-3) in the conscious unrestrained spontaneously hypertensive rat (SHR). Male SHRs were placed on a control diet or one containing 0.05% of manidipine for 4 weeks. Age-matched Wistar-Kyoto (WKY) rats placed on a control diet served as normotensive controls. In comparison with control SHRs, manidipine reduced blood pressure (p < 0.01), increased urinary sodium excretion (p < 0.01), and reduced body weight (p < 0.01). Air jet stress elevated arterial pressure and increased RBF. The pressor response was enhanced more in the control SHRs than in the WKY rats (p < 0.01) and was not altered by manidipine. The percent fall in RBF in the manidipine-treated SHRs (-16%) was less than that in the control SHRs (-30%, p < 0.05) and similar to that in the WKY rats (-18%). In contrast, the pressor effect and the percent fall in RBF caused by ANG II (0.1 nmol/kg/min) were similar in the three groups. Intravenous ET-3 (1 nmol/kg) caused a transient fall, followed by a sustained increase in systemic blood pressure, both of which were associated with a decrease in RBF. The RBF response to ET-3 was blunted in SHRs compared to WKYs and was not altered by manidipine treatment. These results suggest that antihypertensive therapy with manidipine may be beneficial in maintaining RBF during emotional stress.
对情绪应激的肾血管收缩反应增强可能与原发性高血压的发病机制有关。我们研究了慢性马尼地平治疗对清醒不受限制的自发性高血压大鼠（SHR）肾血流量（RBF）对空气喷射应激、血管紧张素II（ANG II）和内皮素-3（ET-3）反应的影响。雄性SHR被置于对照饮食或含0.05%马尼地平的饮食中4周。置于对照饮食的年龄匹配的Wistar-Kyoto（WKY）大鼠作为正常血压对照。与对照SHR相比，马尼地平降低了血压（p<0.01），增加了尿钠排泄（p<0.01），并降低了体重（p<0.01）。空气喷射应激使动脉压升高并增加了RBF。对照SHR的升压反应比WKY大鼠增强得更多（p<0.01），且不受马尼地平影响。马尼地平治疗的SHR中RBF下降百分比（-16%）低于对照SHR（-30%，p<0.05），与WKY大鼠（-18%）相似。相反，ANG II（0.1 nmol/kg/min）引起的升压作用和RBF下降百分比在三组中相似。静脉注射ET-3（1 nmol/kg）导致短暂下降，随后全身血压持续升高，两者均与RBF降低有关。与WKY相比，SHR对ET-3的RBF反应减弱，且不受马尼地平治疗影响。这些结果表明，在情绪应激期间，用马尼地平进行抗高血压治疗可能有助于维持RBF。
