Höllerhage H G, Gaab M R, Zumkeller M, Walter G F
Department of Neurosurgery, Hannover Medical School, West Germany.
J Neurosurg. 1988 Dec;69(6):919-22. doi: 10.3171/jns.1988.69.6.0919.
Twenty anesthetized rats were randomly assigned to a nimodipine-treated group or a control group of 10 rats each. Local cerebral blood flow (lCBF) was measured by means of a surface electrode using the hydrogen clearance technique. Systemic arterial pressure (SAP) was varied with administration of norfenefrine or by hemorrhage in order to obtain SAP/cerebral blood flow (CBF) curves under different conditions. In the control group, a typical autoregulation curve was obtained with an lCBF plateau between 70 and 120 mm Hg SAP. The nimodipine-treated animals, however, showed only a slight diminution in the slope of the curve but no real plateau, indicating impairment of CBF autoregulation. In another series, 20 anesthetized rats were randomly assigned to a treatment group or a control group of 10 animals each. Intravenous Evans blue dye was used as a tracer for blood-brain barrier (BBB) function. In both groups, SAP was raised to a level of 180 mm Hg with administration of norfenefrine for 6 minutes. Extravasation of significantly more Evans blue dye was observed in the nimodipine group than in the control group, indicating impairment of the BBB. It is concluded that nimodipine may impair CBF autoregulation, allowing damage to the BBB under hypertensive conditions.
将20只麻醉大鼠随机分为尼莫地平治疗组和对照组，每组10只。采用氢清除技术通过表面电极测量局部脑血流量（lCBF）。通过给予去甲肾上腺素或放血来改变体循环动脉压（SAP），以便在不同条件下获得SAP/脑血流量（CBF）曲线。在对照组中，获得了一条典型的自动调节曲线，lCBF在SAP为70至120 mmHg之间时保持平稳。然而，尼莫地平治疗的动物曲线斜率仅略有减小，但没有真正的平稳期，表明CBF自动调节受损。在另一组实验中，将20只麻醉大鼠随机分为治疗组和对照组，每组10只。静脉注射伊文思蓝染料作为血脑屏障（BBB）功能的示踪剂。在两组中，通过给予去甲肾上腺素6分钟将SAP提高到180 mmHg的水平。与对照组相比，尼莫地平组观察到更多的伊文思蓝染料外渗，表明BBB受损。得出的结论是，尼莫地平可能会损害CBF自动调节，在高血压条件下导致BBB损伤。
