Effect of sepsis on vecuronium-induced inhibition of acetylcholine release in neuromuscular junction in rats

Abstract

Objective To investigate the effect of sepsis on vecuronium-induced inhibition of acetylcholine release in neuromuscular junction in rats. Methods Thirty-six adult male SPF Sprague-Dawley rats, aged 2-3 months, weighing 200-220 g, were randomly divided into 3 groups (n=12 each) using a random number table: control group (group C), sham operation group (group S) and sepsis group (group Sep). Sepsis was induced by cecum ligation and puncture (CLP) in rats anesthetized with intraperitoneal chloral hydrate 350 mg/kg. At 12 h after CLP, the sciatic nerve-pretibial muscle was prepared. Vecuronium was added to the culture medium with the final concentration of 0.08 μg/ml, and the sciatic nerve-pretibial muscle was incubated for 15 min. Before and after administration, evoked endplate potentials (EPPs) and miniature endplate potentials (MEPPs) were recorded by using intracellular microelectrode. EPP/MEPP ratio was calculated. Results Compared to C and S groups, EPPs, MEPPs and EPP/MEPP ratio were significantly increased before and after administration in group Sep. EPPs, MEPPs and EPP/MEPP ratio were significantly lower after administration than before administration in the three groups. Conclusion Sepsis can promote acetylcholine release in neuromuscular junction, thus weakening vecuronium-induced inhibition of acetylcholine release in neuromuscular junction in rats. Key words: Sepsis; Acetylcholine; Neuromuscular nondepolarizing agents