正常血压大鼠(MAP=93±5毫米汞柱)及两肾单夹,高血压模型大鼠(MAP=116±5毫米汞柱)用氯醛糖-氯脲麻醉后作大脑横切。六小时后苏醒,将右侧提睾肌浸浴在恒定条件的Kreb’s水浴中(pH7.4,PGO_2=40毫米汞柱)。水浴中氧压(PO_2)在10到95毫米汞柱之间,约按10毫米汞柱增加。第一、二、三(A_1、A_2、A_3)级微动脉的管径反应,用闭路电视显微系统测量。当水浴中PO_2增加时,所有大鼠均发生持续性的A_1～A_3级微动 Normal rats (MAP = 93 ± 5 mmHg) and two nephron single-clip, hypertensive rats (MAP = 116 ± 5 mmHg) were anesthetized with chloralose-chlorobromide for brain transection. Six hours later waking, the right cremaster muscle was immersed in a constant-condition Kreb’s water bath (pH 7.4, PGO 2 = 40 mmHg). The oxygen pressure (PO_2) in the water bath is between 10 and 95 mm Hg, about 10 mm Hg. The first, second, third (A_1, A_2, A_3) grade arteriole caliber responses were measured with a CCTV microscopy system. When the PO_2 in water bath increased, all of the rats developed persistent A_1-A_3 micro-mobility