Effects of difference in amount of exercise training on prevention of diabetes mellitus in the Otsuka-Long-Evans-Tokushima Fatty rats, a model of spontaneous non-insulin-dependent diabetes mellitus

• Published in: Diabetes research and clinical practice Vol. 23; no. 3; pp. 147 - 154
• Main Authors: Shima, K., Shi, K., Mizuno, A., Sano, T., Ishida, K., Yoshimoto, S.
• Format: Journal Article
• Language: English
• Published: Ireland Elsevier Ireland Ltd 01.04.1994
• Subjects: Abdominal fat; Animals; Blood Glucose - analysis; Body Weight; Diabetes Mellitus, Type 2 - pathology; Diabetes Mellitus, Type 2 - prevention & control; Disease Models, Animal; Exercise; Glucose Tolerance Test; Insulin resistance; Islets of Langerhans - pathology; Male; NIDDM; Physical Conditioning, Animal; Rats; Rats, Mutant Strains; Sedentary; Insulin resistance; Abdominal fat; Exercise; Sedentary; NIDDM
• ISSN: 0168-8227; 1872-8227
• DOI: 10.1016/0168-8227(94)90098-1

Exercise training every day has been shown to be effective in preventing the development of non-insulin-dependent diabetes mellitus (NIDDM) in a model rat (Otsuka Long Evans Tokushima Fatty (OLETF)). For determination of whether less vigorous exercise training also has a protective effect against the development of NIDDM in this model, seven male OLETF rats each were assigned to training every other day, every 3 days and every 7 days from 6 to 30 weeks of age. At 30 weeks of age, rats trained every other day, 3 days, 7 days and sedentary rats weighed averages of 547, 548, 603 and 695 g and had abdominal fat deposits of 28, 24, 32 and 72 g, respectively. The mean meterages of running of rats trained every other day, 3 days and 7 days over the whole experimental period were 9630, 5166 and 1685 m/week, respectively. At 30 weeks of age, the cumulative incidence of NIDDM in sedentary rats was 85.7% ( 6 7 ), while none of the trained rats became diabetic except for one of rats trained every 7 days. The glucose infusion rate (GIR), an index of insulin sensitivity, in the group trained every 7 days, 60.6 ± 5.0 μmol · kg −1 · min −1, was significantly greater than that in the sedentary group, 21.7 ± 1.7 μmol · kg −1 · min −1. Morphological studies on the pancreas of rats trained every other day and every 3 days showed minimal changes of islets, whereas sections of islets from rats trained every 7 days appeared enlarged and fibrotic, though significantly less so than the islets of sedentary rats. These results demonstrate that less vigorous exercise, such as once a week, is effective for reducing the incidence of NIDDM in this model.