Fig 4. Serial administration of atropine, MRS2500, L-NNA, and TTX under EFS on circular and longitudinal human gastric fundus muscles (10 Hz, 150 V, 0.3 ms and 20 s).

(A) A representative tracing of EFS-evoked motor responses of circular muscle. NOS inhibitor reverses the EFS-induced relaxation. (B)A typical tracing of EFS-evoked motor responses of longitudinal muscle. EFS-induced relaxation is also reversed by L-NNA.