A non-selective cationic channel activated by diacylglycerol in mouse intestinal myocytes

Application of 1-oleoyl-2-acetyl-sn-glycerol (OAG), an analogue of diacylglycerol (DAG) formed via M3 muscarinic receptors, induced inward cationic currents via a protein kinase C-independent mechanism and produced membrane depolarization with increased action potential discharges in mouse intestinal myocytes. Outside-out patches from the myocytes responded to OAG with openings of 115-pS channels characterized by a mean open time (Oτ) of 0.15 ms. M3 receptor stimulation is reportedly capable of causing brief openings (Oτ = 0.23 ms) of 120-pS cationic channels in intestinal myocytes, thus the present results strongly support the idea that the M3-mediated 120-pS channel opening is brought about via DAG-dependent mechanisms.