Overbeck H W
Department of Medicine, University of Alabama, Birmingham 35294.
Am J Physiol. 1988 Feb;254(2 Pt 2):H230-7. doi: 10.1152/ajpheart.1988.254.2.H230.
To study inotropic effects of blood from one-kidney, one-clip (1K,1C) rats with early (less than 7 days) or chronic (greater than 4 wk) benign hypertension, we assessed arteriolar resistance and norepinephrine (NE) responses in vascularly isolated, innervated assay hindlimb vascular beds of alpha-chloralose-anesthetized, normal male recipient rats. Hindlimbs were cross-perfused (2 ml/min) with blood from anesthetized donor rats with limb outflow returned to the donor rat. Perfusion pressure was monitored. Complete NE (injected intra-arterially) dose-response curves in limbs perfused with donor blood from nine early 1K,1C rats, compared with nine appropriate normotensive control donor rats, indicated unchanged thresholds, 50% effective doses, and maximal responses. Curves in limbs perfused with blood from 10 chronic 1K,1C, compared with 10 appropriate controls, suggested small (P less than 0.02) leftward shifts. Decreases (P less than 0.01) in maximal responses were also observed. Limb resting resistance and minimal resistance (sodium nitroprusside) did not rise, even after 4-5 h of cross-perfusion. These results provide no evidence in early 1K,1C and little evidence in chronic 1K,1C that humoral factors, including ouabainlike inhibitors, evoke physiologically significant inotropic effects in arterioles in vivo.
为了研究早期（小于7天）或慢性（大于4周）良性高血压的单肾单夹（1K，1C）大鼠血液的变力作用，我们在α-氯醛糖麻醉的正常雄性受体大鼠的血管分离、有神经支配的测定后肢血管床中评估了小动脉阻力和去甲肾上腺素（NE）反应。后肢用来自麻醉供体大鼠的血液进行交叉灌注（2毫升/分钟），肢体流出物回流到供体大鼠。监测灌注压力。与九只合适的正常血压对照供体大鼠相比，在灌注来自九只早期1K，1C大鼠供体血液的肢体中，完整的NE（动脉内注射）剂量反应曲线表明阈值、50%有效剂量和最大反应没有变化。与十只合适的对照相比，在灌注来自十只慢性1K，1C大鼠血液的肢体中的曲线显示有小的（P小于0.02）左移。还观察到最大反应降低（P小于0.01）。即使在交叉灌注4至5小时后，肢体静息阻力和最小阻力（硝普钠）也没有升高。这些结果表明，在早期1K，1C大鼠中没有证据，在慢性1K，1C大鼠中只有很少证据表明包括哇巴因样抑制剂在内的体液因子在体内小动脉中引起具有生理意义的变力作用。
