AIM: To investigate the characteristics of slow electrical waves and the presence of transient receptor potential melastatin-type 7 (TRPM7) in the human gastrointestinal (GI) tract.
METHODS: Conventional microelectrode techniques were used to record intracellular electrical responses from human GI smooth muscle tissue. Immunohistochemistry was used to identify TRPM7 channels in interstitial cells of Cajal (ICCs).
RESULTS: The human GI tract generated slow electrical waves and had ICCs which functioned as pacemaker cells. Flufenamic acid, a nonselective cation channel blocker, and 2-APB (2-aminoethoxydiphenyl borate) and La3+, TRPM7 channel blockers, inhibited the slow waves. Also, TRPM7 channels were expressed in ICCs in human tissue.
CONCLUSION: These results suggest that the human GI tract generates slow waves and that TRPM7 channels expressed in the ICCs may be involved in the generation of the slow waves.