sympathectomy英 [,sɪmpə'θektəmɪ] 美 [,sɪmpə'θɛktəmi]
释 义 n. 交感神经切除术
例 句 Objective : To investigate the change of enzyme and twitch muscle fiber in spasmodic muscle after sympathectomy. 目的：探讨交感神经切断后，痉挛肌肉内酶与肌纤维结构的改变。
作者： Candace M Reno
The contribution of the sympathetic (SNS) versus parasympathetic (PSNS) nervous system in mediating fatal cardiac arrhythmias during insulin-induced severe hypoglycemia is not well understood. Therefore, experimental protocols were performed in non-diabetic, Sprague Dawley rats to test SNS with 1) adrenal demedullation and 2) chemical sympathectomy, and to test PSNS with 3) surgical vagotomy, 4) nicotinic receptor (mecamylamine) and muscarinic receptor (AQ-RA 741) blockade, and 5) heart perfusions with normal or low glucose, acetylcholine and/or mecamylamine. In protocols 1-4, 3-hour hyperinsulinemic (0.2U·kg·min)-hypoglycemic (10-15 mg/dl) clamps were performed. Adrenal demedullation and chemical sympathectomy had no effect on mortality or arrhythmias during severe hypoglycemia compared to controls. Vagotomy led to a 6.9-fold decrease in mortality, reduced 1 and 2 degree heart block 4.6- and 4-fold, respectively, and prevented 3 degree heart block compared to controls. Pharmacological blockade of nicotinic receptors, but not muscarinic receptors, prevented heart block and mortality versus controls. heart perfusions demonstrated that neither low glucose nor acetylcholine alone caused arrhythmias, but their combination induced heart block that could be abrogated by nicotinic receptor blockade. Taken together, acetylcholine activation of nicotinic receptors via the vagus nerve is the primary mediator of severe hypoglycemia-induced fatal cardiac arrhythmias.