Yoshioka M, Togashi H, Matsumoto M, Minami M, Saito H
First Department of Pharmacology, Hokkaido University, School of Medicine, Sapporo, Japan.
Clin Exp Hypertens A. 1989;11(1):137-47. doi: 10.3109/10641968909035296.
The present study was undertaken to elucidate the effect of selective alpha-1 adrenoceptor antagonist, bunazosin, on sympathetic nerve activity in anesthetized rats. Intravenous administration of bunazosin (10 micrograms/kg) produced a reduction of mean arterial pressure with a significant decrease in heart rate. Accompanied with its hypotension and bradycardia, bunazosin caused a decrease in inferior cardiac nerve activity. On the other hand, renal nerve activity, which reflects vasoconstriction, was not significantly decreased by bunazosin. These findings suggest that bunazosin may possess an anti-tachycardic action resulting from the reduction of cardiac sympathetic nerve activity and that the sympathoinhibitory action of bunazosin may not contribute to its hypotensive action.
本研究旨在阐明选择性α-1肾上腺素能受体拮抗剂布那唑嗪对麻醉大鼠交感神经活动的影响。静脉注射布那唑嗪（10微克/千克）可使平均动脉压降低，心率显著下降。伴随着其低血压和心动过缓，布那唑嗪使心下神经活动降低。另一方面，反映血管收缩的肾神经活动并未因布那唑嗪而显著降低。这些发现表明，布那唑嗪可能具有因心脏交感神经活动降低而产生的抗心动过速作用，且布那唑嗪的交感神经抑制作用可能对其降压作用无贡献。
