脑室注射可乐定和Bay 1470对清醒高血压猫心血管系统的影响。
The cardiovascular effects of intraventricular clonidine and Bay 1470 in conscious hypertensive cats.
作者信息
Finch L
出版信息
Br J Pharmacol. 1974 Nov;52(3):333-8.
1 Intraventricular administration of clonidine (5-30 mug) and an analogue, BAY 1470 (15-30 mug) to conscious renal hypertensive cats produced a fall in mean blood pressure lasting for approximately 3 hours. This fall in blood pressure was accompanied by a marked bradycardia.2 Pretreatment with intraventricular phentolamine (100-200 mug), piperoxan (40-200 mug) or tolazoline (75-200 mug) abolished the cardiovascular effects of intraventricular clonidine (20 mug).3 The cardiovascular effects of intraventricular clonidine (20 mug) were not modified by the pretreatment with either haloperidol (1 mg/kg i.p.) or desmethylimipramine (1 mg/kg i.p.).4 Emesis was observed 1-2 min after the administration of either clonidine (5-20 mug) or BAY 1470 (30 mug). This preceded the cardiovascular actions and was still seen after pretreatment with haloperidol, desmethylimipramine, phentolamine, piperoxan or tolazoline.5 It is concluded that the centrally mediated cardiovascular responses observed after intraventricular administration of small doses of clonidine are due to stimulation of central alpha-adrenoceptors and are independent of central catecholamine uptake mechanisms and dopamine receptors.
向清醒的肾性高血压猫脑室内注射可乐定（5 - 30微克）及其类似物BAY 1470（15 - 30微克），可使平均血压下降，持续约3小时。血压下降伴有明显的心动过缓。
预先脑室内注射酚妥拉明（100 - 200微克）、哌罗克生（40 - 200微克）或妥拉唑啉（75 - 200微克）可消除脑室内注射可乐定（20微克）的心血管效应。
预先腹腔注射氟哌啶醇（1毫克/千克）或去甲丙咪嗪（1毫克/千克）对脑室内注射可乐定（20微克）的心血管效应无影响。
注射可乐定（5 - 20微克）或BAY 1470（30微克）后1 - 2分钟出现呕吐。这先于心血管作用，且在预先用氟哌啶醇、去甲丙咪嗪、酚妥拉明、哌罗克生或妥拉唑啉处理后仍可见到。
结论是，脑室内注射小剂量可乐定后观察到的中枢介导的心血管反应是由于中枢α - 肾上腺素能受体的刺激，且独立于中枢儿茶酚胺摄取机制和多巴胺受体。
Zotero 插件