The Effects of Mivacurium on Isolated Rat Tracheal Muscle / 대한마취과학회지

ABSTRACT

BACKGROUND: Neuromuscular blocking drugs are designed to specifically block nicotinic cholinergic receptors at the neuromuscular junction, but many bind to muscarinic cholinergic receptors on ganglia, nerve endings, and smooth muscles, thereby altering parasymphathetically mediated airway caliber and heart rate. METHODS: We studied the effects of mivacurium on the tension of tracheal smooth muscle by using an isolated rat tracheal preparation. We studied the cumulative effect of acetylcholine after pretreating the tracheal smooth muscle with mivacurium at different concentrations, as well as the effect of L-NAME and propranolol on the tension of tracheal smooth muscle after pretreating with mivacurium. RESULTS: Mivacurium shifted the acetylcholine dose-response curve to the right. L-NAME and propranolol had no effect on the tension of tracheal smooth muscle after pretreating with mivacurium. CONCLUSIONS: We have found that mivacurium relaxes isolated rat tracheal smooth muscle and this effect has no relationship to beta-receptors or nitric oxide.