Objective To investigate the alteration of contractile and relaxant responses of the isolated gastric smooth muscle in early type 1 diabetic rats.Methods Male SD rats were administrated 65 mg/kg sterptozocin(STZ) by intraperitoneal injection. Using the method of organ bath, contractile and relaxant responses were induced by electric field stimulation(EFS) and agonists on gastric smooth muscle in rats, we observe the alterations of contractile and relaxant responses of the gastric smooth muscle in early type 1 diabetic rats.Results(1) In type 1 diabetic rats, the contractile responses were decreased, and the contractile amplitudes were disordered significantly, compared with that of in normal rats(P<0.05);(2) There were no differences in the EFS-induced contractions on gastric body smooth muscle and the spontaneous contractions on gastric antrum in normal rats and type 1 diabetic rats;(3) Compared with normal rats, both the relaxations on gastric fundus smooth muscle, and the contractions on pylorus circular muscle were increased in type 1 diabetic rats(P<0.01).Conclusions Based on the changes of contractile and relaxant responses on gastric smooth muscle in STZ-induced type 1 diabetic 4 weeks rats, the damages of gastric fundus and pylorus seem to occur first, and the alterations of neuromodulation are main reason, which affects the contractile and relaxant functions of gastric smooth muscle in early type 1 diabetic rats.