Lack in Effects of Therapeutic Concentrations of Dexmedetomidine and Clonidine on the Neuromuscular Blocking Action of Rocuronium in Isolated Rat Diaphragms
Lack in Effects of Therapeutic Concentrations of Dexmedetomidine and Clonidine on the Neuromuscular Blocking Action of Rocuronium in Isolated Rat Diaphragms
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DOI：
10.1213/01.ane.0000260317.02748.83
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发表时间：
2007-05
影响因子：
5.7
通讯作者：
E. Narimatsu;T. Niiya;M. Kawamata;A. Namiki
中科院分区：
文献类型：
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作者：
E. Narimatsu;T. Niiya;M. Kawamata;A. Namiki
背景技术背景：我们研究了-2肾上腺素受体激动剂可乐定和右美托咪定对罗库溴铵神经肌肉阻滞作用的影响。方法：等距抽搐紧张的大鼠神经半膈制备引起的间接（膈神经）超大刺激在0.1 Hz进行了评价。研究结果：可乐定和右美托咪定50 M（n = 6）使罗库溴铵浓度-抽搐张力曲线左移，50%抽搐抑制时的罗库溴铵浓度（IC 50）较对照组降低（n = 9，P < 0.01）。可乐定50 M或右美托咪定50 M引起的E2移位不能被育亨宾50 M（一种肾上腺素受体拮抗剂）所拮抗。7 M罗库溴铵可部分抑制抽搐张力，约为对照组的65%，而浓度为30 M或更高的可乐定（n = 6）和右美托咪定（n = 9）则以浓度依赖性方式进一步抑制抽搐张力（P < 0.01）。结论：这些结果表明，非常高浓度的可乐定和右美托咪定可增强罗库溴铵的神经肌肉阻滞作用，但不是通过对-2肾上腺素受体的激动剂作用介导的。
BACKGROUND: We investigated the effects of the -2 adrenoceptor agonists clonidine and dexmedetomidine on the neuromuscular blocking effect of rocuronium in vitro. METHODS: Isometric twitch tensions of rat nerve–hemidiaphragm preparations elicited by indirect (phrenic nerve) supramaximal stimulation at 0.1 Hz were evaluated. RESULTS: Clonidine and dexmedetomidine 50 M (n = 6 each), but not 0.05 M, shifted the rocuronium concentration–twitch tension curves to the left and decreased the rocuronium concentration for 50% twitch depression (IC50) compared with control (n = 9, P < 0.01). The leftward shift induced by clonidine 50 M or dexmedetomidine 50 M was not antagonized by yohimbine 50 M, an -2 adrenoceptor antagonist. Twitch tensions partially depressed by 7 M rocuronium, to about 65% of the control, were further suppressed in a concentration-dependent manner by clonidine (n = 6) and dexmedetomidine (n = 9) at concentrations of 30 M or more (P < 0.01). CONCLUSIONS: These results indicate that very high, but not therapeutic, concentrations of clonidine and dexmedetomidine enhance the neuromuscular blocking action of rocuronium, but this is not mediated by an agonist action on -2 adrenoceptors.