Studies on regulating factors of cerebral blood flow during cerebral ischemia

脑缺血时脑血流调节因素的研究

• 批准号: 01570042
• 负责人: TAKEUCHI Toru
• 金额: $ 1.34万
• 依托单位: Yamanashi Medical College
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1989
• 资助国家: 日本
• 起止时间: 1989 至 1991
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-01570042/
• 关键词: Parietal cortex tissue blood flow; Systemic arterical pressure; Hypoxic, hyperoxic and hypercapnic loadings; Renal nerve activity; Vasomotor center activating factor; Blood flow in rostral ventrolateral medulla; Tissue PO_2, PCO_2, pH in rostral ven

1. Even when the blood supply to the rabbit brain was restricted to a sole route of the internal carotid artery on one side, the parietal cortex tissue blood flow(CTF)kept 97% of the control value.2. The relationship between systemic arterial pressure(SAP)and CTF was described by a linear regression equation.3. The magnitude of increase in tissue PCO_2 in the rostral ventrolateral medulla(RVLM)during complete interruption of blood supply to the brain for one minute equalled that of increase in the tissue PCO_2 in RVLM during inhalation of 2% CO_2 air mixture.4.5% CO_2 air mixture inhalation increased significantly tissue PCO_2 in the RVLM and decreased significantly interstitial pH, and also increased significantly blood flow in the RVLM, renal nervous activity(RNA)and SAP. The 5% CO_2 loading influenced nothing on the increasing patterns of RNA and SAP caused by graded cerebral ischemia.5.8% O_2 and 90% O_2 gas mixture inhalations induced respectively significant decrease and increase in tissue PO_2 in the RVLM. The 8% O_2 loading increased significantly blood flow in the RVLM. The 8% O_2 loading and 90% O_2 loading induced respectively marked increase and strong attenuation in both RNA and SAP rises caused by cerebral ischemia. The results obtained by multiple linear regression analysis indicated that severe hypoxia was the main factor activating the vasomotor center in the RVLM when the RVLM was exposed to ischemia.6. Blood vessels in the RVLM were dilated strongly by cerebral ischemia and thus the blood vessels in the RVLM during cerebral ischemia did not respond significantly to hypoxic and hypercapnic loadings.

1.即使兔脑的血供仅限于一侧颈内动脉，顶叶皮质组织血流量（CTF）仍保持对照值的97%.系统动脉压（SAP）与CTF之间的关系可用线性回归方程描述.完全阻断脑血供1 min时，延髓头端腹外侧区（RVLM）组织中PCO_2的增加幅度与吸入2%CO_2混合气时相当。吸入4.5%CO_2混合气时，RVLM组织中PCO_2显著增加，间质pH显著降低，并能显著增加RVLM血流量、肾神经活动（RNA）和SAP。5%CO_2负荷对分级脑缺血引起的RNA和SAP的增加模式无影响，5.8%O_2和90%O_2混合气体吸入分别引起RVLM组织PO_2的显著降低和升高。8%O_2负荷使RVLM血流量明显增加。8%O_2负荷和90%O_2负荷分别使脑缺血引起的RNA和SAP升高显著增加和明显减弱。多元线性回归分析结果表明，重度缺氧是RVLM缺血时激活血管中枢的主要因素. RVLM中的血管被脑缺血强烈扩张，因此在脑缺血期间RVLM中的血管对低氧和高碳酸负荷没有显著反应。

项目成果

Takeuchi, T.: "Compensatory adjustment in blood flow of the rabbit cerebral cortex during graded cerebral ischemia." Jpn. J. Physiol.40. 665-677 (1990)

Takeuchi, T.：“分级脑缺血期间兔子大脑皮层血流的代偿性调整。”

Takeuchi,T.: "Compensatory adjustment in blood flow of the rabbit cerebral cortex during graded cerebral ischemia." Japanese Journal of Physiology. 40. 665-677 (1990)

Takeuchi,T.：“分级脑缺血期间兔子大脑皮层血流的代偿性调整。”

Takeuchi,T.: "Compensatory adjustment in blood flow of the rabbit cerebral cortex during graded cerebral ischemia." Japanese Journal of Physiology.40. 665-677 (1990)

Takeuchi,T.：“分级脑缺血期间兔子大脑皮层血流的代偿性调整。”

Toru TAKEUCHI: "Compensatory Adjustment in Blood Flow of the Rabbit Cerebral Cortex during Graded Cerebral Ischemia." Japanese Journal of Physiology. 40. 665-677 (1990)

Toru TAKEUCHI：“分级脑缺血期间兔子大脑皮层血流的补偿性调整。”

Takeuchi,T.: "Effects of hypoxia,hyperoxia and hypercapnia on cerebral ischemic response in anesthetized rabbits."

Takeuchi,T.：“缺氧、高氧和高碳酸血症对麻醉兔子脑缺血反应的影响。”