The effects of intravenous anaesthetics on the cardiovascular system of the rabbit.
1 A pithed rabbit preparation is described that allows selective stimulation of the vertebral outflows. 2 The responses to stimulation of sympathetic vasopressor fibres were blocked by hexamethonium and phentolamine but potentiated by cocaine, whereas the responses to stimulation of cardioaccelerator fibres were blocked by propranolol. 3 Ketamine, althesin and pentobarbitone enhanced the effects of noradrenaline and attenuated the effects of sympathetic nerve stimulation. Thiopentone enhanced the effects of both noradrenaline and sympathetic nerve stimulation. 4 In pithed rabbits a transient, dose-related cardiovascular depression was produced by each agent irrespective of whether vasomotor tone was present whereas in decerebrate rabbits the corresponding cardiovascular depression was longer lasting. 5 It is concluded that the cardiovascular depression produced by intravenous anaesthetics in intact rabbits is due to a combination of central and peripheral effects.
D000530:Alfaxalone Alfadolone Mixture / Q000494:pharmacology; D000777:Anesthetics / Q000008:administration & dosage / Q000494:pharmacology*; D000818:Animals; D001341:Autonomic Nervous System / Q000502:physiology; D003042:Cocaine / Q000494:pharmacology; D003655:Decerebrate State / Q000503:physiopathology; D004558:Electric Stimulation; D006439:Hemodynamics / Q000187:drug effects*; D007275:Injections, Intravenous; D007649:Ketamine / Q000494:pharmacology; D008297:Male; D010424:Pentobarbital / Q000494:pharmacology; D011817:Rabbits; D013564:Sympathetic Nervous System / Q000187:drug effects; D013874:Thiopental / Q000494:pharmacology
D000777:Anesthetics; D007649:Ketamine; D000530:Alfaxalone Alfadolone Mixture; D010424:Pentobarbital; D003042:Cocaine; D013874:Thiopental