Complementary Effects of Paeoniflorin and Glycyrrhizin on Intracellular Call Mobilization in the Nerve-Stimulated Skeletal Muscle of Mice

Abstract

Effects of paeoniflorin (PF) and glycyrrhizin (GLR), contained in paeony and licorice roots, respectively, on contractile and non-contractile Ca²⁺ mobilization were examined by measuring the Ca²⁺-aequorin luminescence (Ca²⁺ transients) of the nerve-stimulated skeletal muscle of mice in the presence of neostigmine (0.3 μM). PF (0.1-1 mM) prolonged the duration of non-contractile Ca2²⁺ transients, which may induce the desensitization of nicotinic acetylcholine receptor, but did not affect contractile Ca2²⁺ transients. GLR (0.3-1 mM) depressed contractile Ca²⁺ transients without affecting non-contractile transients. These results suggest that PF and GLR may have complementary effects on intracellular Ca²⁺ mobilization to block the neuromuscular transmission.