Dopaminergic receptors (DRs) are existed in the enteric nervous system (ENS) including submucosal plexus.Whether the DR in submucosal plexus involves in the regulation of DA on the colonic :ion transport remains unknown.In the present study short-circuit current (Isc) was performed to investigate the colonic epithelial ion transport.The localization of DRs in enteric neurons was evaluated though immunofluorescence.The results indicated that pretreatment of colonic mucosa/submucosa preparations with TTX, DA-induced Isc downward deflection were increased from-10.1±3.8 μAlcm2 to-15.8±2.1 μA/cm2 (n=6).In the presence of forsklin, adenylyl cyclase activator, DA-induced Isc response curve was sustained and transient in the pretreatment with and without TTX, respectively.The immunoreactivity(lR) of DR including D1 and D2 was found in the enteric nitrergic neurons.D1-IR was also distributed in the cholinergic neurons.in conclusions, DA may modulate neurotransmitter release from submucosal plexus by binding with DR, ultimately regulate colonic ion transport.