Magnesium sulfate enhances non-depolarizing muscle relaxant vecuronium action at adult muscletype nicotinic acetylcholine receptor in vitro

• Published in: 中国药理学报：英文版 Vol. 32; no. 12; pp. 1454 - 1459
• Main Author: Hong WANG Qi-sheng LIANG Lan-ren CHENG Xiao-hong LI Wei FU Wen-tao DAI Shi-tong LI
• Format: Journal Article
• Language: English
• Published: 2011
• Subjects: HEK293细胞; 乙酰胆碱受体; 体外; 去极化; 成人; 硫酸镁; 肌肉松弛剂; 铵
• ISSN: 1671-4083; 1745-7254

Aim： To investigate the effect of magnesium sulfate and its interaction with the non-depolarizing muscle relaxant vecuronium at adult muscle-type acetylcholine receptors in vitro. Methods： Adult muscle-type acetylcholine receptors were expressed in HEK293 cells. Drug-containing solution was applied via a gravity-driven perfusion system. The inward currents were activated by brief application of acetylcholine （ACh）, and recorded using whole-cell voltage-clamp technique. Results： Magnesium sulfate （1-100 mmol/L） inhibited the inward currents induced ACh （10 pmol/L） in a concentration-dependent manner （IC5o=29.2 mmol/L）. The inhibition of magnesium sulfate was non-competitive. In contrast, vecuronium produced a potent inhibition on the adult muscle-type acetylcholine receptor （ICso=8.7 nmol/L） by competitive antagonism. Magnesium sulfate at the concentrations of 1, 3, and 6 mmol/L markedly enhanced the inhibition of vecuronium （10 nmol/L） on adult muscle-type acetylcholine receptors. Conclusion： Clinical enhancement of vecuronium-induced muscle relaxation by magnesium sulfate can be attributed partly to synergism between magnesium sulfate and non-depolarizing muscle relaxants at adult muscle-type acetylcholine receptors.