Shiokawa O, Sadoshima S, Okada Y, Nagao T, Fujishima M
Second Department of Internal Medicine, Faculty of Medicine, Kyushu University, Fukuoka, Japan.
Gerontology. 1989;35(2-3):106-12. doi: 10.1159/000213007.
The effects of alpha- and beta-adrenergic receptors on the lower limits of cerebral (CBF) and cerebellar blood flow (CeBF) autoregulation were examined in spontaneously hypertensive rats. CBF and CeBF were measured during hemorrhagic hypotension in rats treated with adrenergic blockers, phenoxybenzamine (PBZ) or propranolol (PPL), using a hydrogen clearance method. The lower limits for CBF beyond which blood flow was decreased steeply were 72% of resting values in the control, 44 in the PBZ and 80 in the PPL group. Similar tendency was also observed for CeBF. In the control group, the reducing rates of mean arterial pressure (MAP) to decrease CBF by 15 and 30% of the resting values were 33% (58 mm Hg) of the resting MAP and 46% (80 mm Hg), respectively, and those to reduce CeBF to the same extent were 35% (61 mm Hg) and 52% (92 mm Hg), respectively. In the PBZ group, the respective reducing rates of MAP were 52% (71 mm Hg) and 65% (88 mm Hg), respectively, for CBF and 50% (68 mm Hg) and 65% (88 mm Hg), respectively, for CeBF. In contrast, in the PPL group, those rates were 22% (39 mm Hg) and 32% (56 mm Hg), respectively, for CBF, and 23% (40 mm Hg) and 30% (52 mm Hg), respectively, for CeBF, being significantly smaller than those in the control and the PBZ groups (p less than 0.01, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)
在自发性高血压大鼠中，研究了α和β肾上腺素能受体对脑血流（CBF）和小脑血流（CeBF）自动调节下限的影响。使用氢清除法，在接受肾上腺素能阻滞剂苯氧苄胺（PBZ）或普萘洛尔（PPL）治疗的大鼠出血性低血压期间测量CBF和CeBF。CBF自动调节下限（超过此值血流会急剧下降）在对照组中为静息值的72%，PBZ组为44%，PPL组为80%。CeBF也观察到类似趋势。在对照组中，将平均动脉压（MAP）降低以使CBF降低静息值的15%和30%时，降低率分别为静息MAP的33%（58毫米汞柱）和46%（80毫米汞柱），将CeBF降低到相同程度时的降低率分别为35%（61毫米汞柱）和52%（92毫米汞柱）。在PBZ组中，CBF的MAP降低率分别为52%（71毫米汞柱）和65%（88毫米汞柱），CeBF的降低率分别为50%（68毫米汞柱）和65%（88毫米汞柱）。相比之下，在PPL组中，CBF的降低率分别为22%（39毫米汞柱）和32%（56毫米汞柱），CeBF的降低率分别为23%（40毫米汞柱）和30%（52毫米汞柱），显著小于对照组和PBZ组（p均小于0.01）。（摘要截断于250字）
