Abstract: Rabbit digestive tract were investigated by the method of immunohistochemical technique and histochemical technique(toluidine blue or neutral red staining).There was immunoreactive positive reaction in rabbit digestive tract except in esophagus part.The 5-HT immunoreactive positive cells were found in epithelium and lamina propria.Mast cells distribute mainly in the mucous membrane or submucosa connective tissues.There are 18%~48% MC in histochemical technique corresponding to 5-HT positive cells in the imm...