Mechanism of motilin-mediated inhibition on voltage-dependent potassium currents in hippocampal neurons.

OBJECTIVE: The effects of motilin on voltage-dependent K+ currents in hippocampal neurons with the addition of L-arginine (L-AA), D-arginine (D-AA) and N-nitro-L-arginine methyl ester (L-NAME) were investigated in this study.

METHODS: Mice (1-3 days old) were randomly assigned to different groups according to the addition of motilin, L-AA, D-AA, and L-NAME. The K+ current signals were detected by the whole-cell patch-clamp technique.

RESULTS: Compared with the control group, the transient outward voltage-dependent K+ current was significantly inhibited by motilin added with L-AA. In contrast, the addition of motilin and L-NAME significantly increased the K+ current, while no significant change was detected by the addition of motilin accompanied with D-AA.

CONCLUSION: The inhibiting effects of motilin on the voltage-dependent K+ current in hippocampal neurons indicate that motilin acts as a regulatory factor for the nitric oxide pathway.