Effect of Tangweian Jianji on the Biomechanical and Morphometric Remodeling of Colon and Rectum in STZ Induced Diabetic Rats

AIM: The aim of the study was to investigate the effect of TWAJJon the biomechanical and morphometrical remodeling of colon andrectum in streptozotocin (STZ) induced diabetic rats.METHODS: The colonic and rectal segments obtained fromdiabetic (DM), TWAJJ treated diabetic (TH, high dosage: 10 g/kg;TL, low dosage: 5 g/kg) and normal (CON) rats were used for thestudy. Blood glucose and serum insulin levels were measured. Atthe end of experiment, the circumferential length, the wall thicknessand the opening angle were measured from the digitized images ofthose segments and residual strain was computed. Circumferentialand longitudinal stresses and strains were computed from the length,diameter and pressure data and from the zero-stress state geometryfor the colonic segment.RESULTS: The glucose and insulin levels did not differ among DM,TH and TL groups. Wet weight, wall thickness, cross-sectional wallarea, opening angle, and absolute values of residual strain of colonicand rectal segments in DM group were significantly higher thanthose in CON group (P<0.05 and P<0.01), whereas those parametersin TH group but not in TL group were significantly lower than thosein DM group (P<0.05, P<0.01). Furthermore, the circumferentialand longitudinal stiffness of the colonic wall increased in DM groupcompared those with CON group. TH but not TL treatment couldsignificantly decrease the colonic wall stiffness in both directions (P<0.01).CONCLUSION: Although TWAJJ (high dose) treatment could notsignificantly correct the changes of blood glucose and serum insulinlevels in the diabetic rats; it could partly restore the morphometricand biomechanical remodeling of lower GI tract caused by diabetes.