自发性高血压大鼠对脑室内注射肾上腺素的心血管反应。

Cardiovascular responses to intraventricular adrenaline in spontaneous hypertensive rats.

作者信息

Borkowski K R, Finch L

出版信息

Eur J Pharmacol. 1978 Feb 1;47(3):281-90. doi: 10.1016/0014-2999(78)90235-2.

Abstract

The effects of intracerebroventricular (i.c.v.) injections of adrenaline on the blood pressure and heart rate of spontaneous hypertensive (SH) rats have been investigated. Adrenaline induced dose-related falls in blood pressure and heart rate in both conscious and urethane anaesthetised rats. In conscious rats, the hypotension and metoprolol, but were unaffected by pretreatment with phentolamine, piperoxan, fluphenazine or methysergide. However, in urethane-anaesthetised rats, the hypotension and bradycardia induced by i.c.v. adrenaline was not significantly affected by i.c.v. pretreatment with propranolol or oxprenolol, while metoprolol significantly antagonised only the bradycardia. Piperoxan, fluphenazine and methysergide were also without effect. Pretreatment with mecamylamine (i.p.) abolished the cardiovascular depressor effects of i.c.v. adrenaline in both conscious and urethane anaesthetised SH rats. It is concluded that the cardiovascular depressor effects of i.c.v. adrenaline are mediated by central adrenoceptors in SH rats and that, in conscious rats, these depressor effects may be mediated by central beta-adrenoceptors rather than alpha-adrenoceptors.

摘要

已经研究了脑室内（i.c.v.）注射肾上腺素对自发性高血压（SH）大鼠血压和心率的影响。肾上腺素在清醒和乌拉坦麻醉的大鼠中均引起与剂量相关的血压和心率下降。在清醒大鼠中，低血压和心动过缓可被美托洛尔逆转，但酚妥拉明、哌罗克生、氟奋乃静或麦角新碱预处理对其无影响。然而，在乌拉坦麻醉的大鼠中，脑室内注射肾上腺素引起的低血压和心动过缓不受脑室内注射普萘洛尔或氧烯洛尔预处理的显著影响，而美托洛尔仅显著拮抗心动过缓。哌罗克生、氟奋乃静和麦角新碱也无作用。美加明（腹腔注射）预处理消除了清醒和乌拉坦麻醉的SH大鼠中脑室内注射肾上腺素的心血管降压作用。结论是，脑室内注射肾上腺素的心血管降压作用由SH大鼠的中枢肾上腺素能受体介导，并且在清醒大鼠中，这些降压作用可能由中枢β-肾上腺素能受体而非α-肾上腺素能受体介导。