title: [Comparison of endocrine effects of hypotension induced by sodium nitroprusside, trimetaphan camsylate and a nitroprusside-trimetaphan mixture in rabbits].
abstract: Endocrine effects of hypotension induced by nitroprusside, trimetaphan and a nitroprusside-trimetaphan mixture were studied in 34 male rabbits under halothane anesthesia. They were randomly divided into four groups; nitroprusside (group N; n = 8), trimetaphan (group T; n = 10), a nitroprusside-trimetaphan mixture (group M; n = 8) and controls (group C; n = 8). No change was noted in plasma catecholamines measured in group C throughout the experiment, but plasma renin activity decreased progressively. During induced hypotension, plasma catecholamines and plasma renin activity of group N were significantly higher than the control value. In contrast, in group T plasma epinephrine decreased significantly. On the other hand, in group M, plasma renin activity showed a slight but not significant increase, while plasma catecholamines remained unchanged. This may have occurred since a mixture of nitroprusside and trimetaphan produced the dissociation of renin-angiotensin-sympathoadrenal loop. In conclusion, these results suggest that a nitroprusside-trimetaphan mixture is a useful method for hypotensive anesthesia by inhibiting the excessive activation of renin-angiotensin-sympathetic system.
authors.forename: S
authors.initials: S
authors.lastname: Takeda
authors.forename: Y
authors.initials: Y
authors.lastname: Inada
authors.forename: T
authors.initials: T
authors.lastname: Tomaru
authors.forename: T
authors.initials: T
authors.lastname: Kagawa
authors.forename: T
authors.initials: T
authors.lastname: Ikeda
authors.forename: N
authors.initials: N
authors.lastname: Mozawa
authors.forename: F
authors.initials: F
authors.lastname: Morimoto
mesh_terms: D000818:Animals; D004338:Drug Combinations; D004837:Epinephrine / Q000097:blood; D005292:Ferricyanides; D007023:Hypotension, Controlled; D009599:Nitroprusside / Q000008:administration & dosage*; D009638:Norepinephrine / Q000097:blood; D011817:Rabbits; D012083:Renin / Q000097:blood; D014294:Trimethaphan / Q000008:administration & dosage*
chemical_list: D004338:Drug Combinations; D005292:Ferricyanides; D009599:Nitroprusside; D014294:Trimethaphan; D012083:Renin; D009638:Norepinephrine; D004837:Epinephrine