体位変換時のウサギ脳循環にatenollolが及ぼす影響
第77回 日本生理学会大会 発表
2000年3月27～29日
於：横浜
| 【演題】 | 体位変換時のウサギ脳循環にatenollolが及ぼす影響Effects of Atenolol on Cerebro-Circulatory Dynamics of Rabbits Caused by Passive Body Tilting |
| 【発表者】 | 加藤 正巳1), 2)、佐竹 裕孝2)、松波 謙一2)1) 株式会社日本バイオリサーチセンター、2) 岐阜大学医学部・反射研KATOH, M.1), 2), SATAKE, H.2) and MATSUNAMI, K.2)
1) Pharmacol. Study Dept., Nihon Bioresearch Inc., Hashima 501-6251, Japan |
| 【内容】 | The cerebral circulatory dynamics were examined in conscious rabbits (Kbl-JW, n=12) when their body were passively tilted from prone to the head-up (+45｡) and/or the head-down (-45｡).Every rabbit was randomly tilted upward and/or downward for 15 minutes from the prone position (15 min; control), and then it returned to prone position as a recovery period (15 min).Firstly the animals untreated, serving as the control, were examined twice according to the above tilting sequence (HU and/or HD), thereafter examined in the same way after a dose of Atenolol at 1mg/kg (i.v.).
The internal carotid flow (ICF) and auricular blood flow (ABF) were measured as well as blood pressure (BP). ECG was also monitored. In the control animals, HR, BP and ABF significantly increased (p<0.01) by the head-down tilting (HDT), while ICF decreased (p<0.05). During head-up tilting (HUT), BP significantly decreased (p<0.01) as well as ABF (p<0.05), but HR increased (p<0.01). No significant difference resulted from Atenolol was observed in the responses of BP during passive tilting. On the contrary, increases in ABF and HR shown in the control animal during HDT disappeared with a dose of Atenolol. Moreover, in case of HUT, the decrease in HR observed in the control also disappeared with Atenolol treatment. It can be concluded, from these results, that the sympathetic activation is concerned with the dynamic responses in cervical and systemic circulation when rabbits are passively tilted, particularly in HDT. |