Day M D, Roach A G
Br J Pharmacol. 1976 Dec;58(4):505-15. doi: 10.1111/j.1476-5381.1976.tb08617.x.
Dopamine (30 and 45 mug) administered intracerebroventricular (i.c.v.) to a group of 10 conscious normotensive cats caused dose-related increases in blood pressure and heart rate. In 4 of these animals the initial cardiovascular stimulant effects of i.c.v. dopamine were followed by hypotension and bradycardia. 2 alpha-Methyldopamine (30 and 45 mug i.c.v.) produced qualitatively similar responses to dopamine except that the cardiovascular stimulant effects were smaller and the secondary depressant effects somewhat more prolonged. 3 Both stimulant and depressant effects of i.c.v. dopamine and alpha-methyldopamine were greatly inhibited by autonomic ganglion blockade or by adrenergic neurone blockade. 4 The cardiovascular stimulant effects of both i.c.v. dopamine and i.c.v. alpha-methyldopamine were selectively inhibited by beta-adrenoceptor blocking agents whilst the cardiovascular depressant effects of these substances were abolished by the alpha-adrenoceptor blocker phentolamine or by the dopamine-beta-hydroxylase inhibitor disulfiram. 5 Haloperidol by either i.c.v. or the intravenous route abolished both cardiovascular stimulant and depressant effects of i.c.v. dopamine, whilst pimozide by either route inhibited only the cardiovascular stimulant effects. 6 In 2 cats, injection of dopamine into the cisterna magna produced predominantly depressant effects on the cardiovascular system except with a higher dose which induced biphasic responses.
向一组10只清醒的正常血压猫脑室内注射多巴胺（30微克和45微克），可引起血压和心率呈剂量相关的升高。在其中4只动物中，脑室内注射多巴胺最初的心血管兴奋作用之后出现了低血压和心动过缓。2α-甲基多巴胺（脑室内注射30微克和45微克）产生了与多巴胺定性相似的反应，只是心血管兴奋作用较小，继发的抑制作用稍长。3脑室内注射多巴胺和α-甲基多巴胺的兴奋和抑制作用均被自主神经节阻断或肾上腺素能神经元阻断大大抑制。4脑室内注射多巴胺和脑室内注射α-甲基多巴胺的心血管兴奋作用均被β-肾上腺素受体阻断剂选择性抑制，而这些物质的心血管抑制作用则被α-肾上腺素受体阻断剂酚妥拉明或多巴胺-β-羟化酶抑制剂双硫仑消除。5通过脑室内或静脉途径给予氟哌啶醇可消除脑室内注射多巴胺的心血管兴奋和抑制作用，而通过任一途径给予匹莫齐特仅抑制心血管兴奋作用。6在2只猫中，向脑大池注射多巴胺对心血管系统主要产生抑制作用，但较高剂量会引起双相反应。
