Prokinetic drugs accelerate gastric emptying in diabetic patients with gastroparesis. Tegaserod, a 5-HT4 partial agonist, increases GI motility by enhancing Ach release from autonomic neurons innervating smooth muscle. Autonomic neuropathy, evident in animal models of diabetes, may alter the efficacy of prokinetic drugs which rely on effective neuromuscular transmission to increase motility. These studies examined the effect of tegaserod on motility of whole thickness rings of fundus and antrum from control (KK) and obese type 2 diabetic Agouti mice (KK.Cg-Aγ) using tissue bath set-up. Tissues were pretreated with vehicle or 4-DAMP (M3 muscarinic receptor antagonist), then treated with bethanechol or tegaserod (TG). Drug responses were quantified as area under the curve (g*s) or peak contraction (g). At 7 weeks after diabetes onset, diabetic mice were heavier (42±1g) than control mice (32±1g). Bethanechol (10 μM)-induced peak contractions of antrum, but not fundus, were reduced in diabetic as compared to control mice [antrum: control (n=11), 1.6±0.2; diabetic (n=10), 1.1±0.1*; *p<0.05][fundus: control (n=9), 2.9±0.3; diabetic (n=11), 2.8±0.3]. In both control and diabetic mice, TG treatment resulted in relaxation of antrum [0.1 μM: control (n=13), 1±1; diabetic (n=12), 3±2] [1.0 μM: control (n=14), -1±1; diabetic (n=12), -1±3] [10 μM: control (n=14), -6±2; diabetic (n=15), -5±3], but contraction of fundus [0.1 μM: control (n=13), 10±3; diabetic (n=11), 6±4] [1.0 μM: control (n=13), 18±6; diabetic (n=11), 31±11] [10 μM: control (n=13), 28±10; diabetic (n=13), 43±13]. 4-DAMP at 0.5 μM was equally effective, but at 1 μM was more effective, in reducing bethanechol (10 μM)induced contractions of fundus from diabetic mice [vehicle: (n=11), 380±58; 0.5 μM: (n= 8), 77±23; 1 μM: (n=8), 12±2*; *p<0.05] as compared to control mice [vehicle: (n=9), 374±53; 0.5 μM: (n=8), 55±14; 1 μM: (n=9), 20±3]. Using fundus, 4-DAMP at 0.5 μM, but not 1 μM, reduced TG (10 μM)-induced contractions in diabetic mice [vehicle: (n=13), 43±13; 0.5 μM: (n=14), 7±8*; 1 μM: (n=14), 13±7; *p<0.05], but not in control mice [vehicle: (n=13), 28±10; 0.5 μM: (n=11), 10±10; 1 μM: (n=11), 24±9]. 4-DAMP (0.5, 1, 10 μM) did not alter TG (10 μM)-induced relaxation of antrum from control or diabetic mice. In diabetic, but not control mice, TG-induced contractions of fundus were reduced by 4-DAMP, suggesting an additional non-cholinergicmechanism for TG-induced contraction in control mice. Both gastric region and type 2 diabetes may alter the effectiveness of prokinetic agents in accelerating gastric emptying. Supported by College of Health Sciences and ORSP at MWU.