Kaukinen S
Acta Anaesthesiol Scand. 1978;22(4):437-46. doi: 10.1111/j.1399-6576.1978.tb01320.x.
The effects of hydralazine, clonidine, propranolol and methyldopa medications on the cardiovascular response to ketamine anaesthesia were studied in spontaneously hypertensive (SH) rats. Except in propranolol- and methyldopa-treated animals, blood pressure was increased by ketamine in all groups. The heart rate was increased only in the normotensive control rats, whereas it was reduced in both the unmedicated and all of the medicated SH rats. Plasma renin activity under ketamine anaesthesia was markedly higher in normotensive control rats than in any of the SH groups. The pressor responses to dopamine and metaraminol were not altered by propranolol medication, but hydralazine suppressed these responses, while they were markedly intensified by clonidine and methyldopa treatment. Similarly, small additional doses of ketamine caused a pressor response only in clonidine- and methyldopa-treated animals, whereas in the other groups the response was depressive. The tolerance to haemorrhagic shock during ketamine anaesthesia was notably improved by hydralazine and methyldopa medication, but impaired by propranolol treatment. The results suggest that, with special reference to shock tolerance, hydralazine and methyldopa, and to a lesser extent also clonidine, have a favourable effect on the circulation under ketamine anaesthesia, whereas the action of beta-blockade may be harmful.
在自发性高血压（SH）大鼠中研究了肼屈嗪、可乐定、普萘洛尔和甲基多巴药物对氯胺酮麻醉下心血管反应的影响。除了普萘洛尔和甲基多巴治疗的动物外，氯胺酮使所有组的血压升高。仅正常血压对照大鼠的心率增加，而未用药和所有用药的SH大鼠的心率均降低。氯胺酮麻醉下正常血压对照大鼠的血浆肾素活性明显高于任何SH组。普萘洛尔用药未改变对多巴胺和间羟胺的升压反应，但肼屈嗪抑制了这些反应，而可乐定和甲基多巴治疗则使其明显增强。同样，小剂量额外的氯胺酮仅在可乐定和甲基多巴治疗的动物中引起升压反应，而在其他组中反应为降压。肼屈嗪和甲基多巴用药显著改善了氯胺酮麻醉期间对失血性休克的耐受性，但普萘洛尔治疗则损害了耐受性。结果表明，特别是在休克耐受性方面，肼屈嗪和甲基多巴，以及在较小程度上可乐定，对氯胺酮麻醉下的循环有有利影响，而β受体阻滞剂的作用可能是有害的。
