Resumo
he present study was aimed at evaluating the effect of continuous exercise (swimming 30th - 90th day of life, 90 min/day, 5 days/week) on the development of obesity in monosodium glutamate (MSG) treated rats. For this, male Wistar rats were divided in 4 groups: CS - Control Sedentary, CE - Control Exercised, MS - MSG Sedentary and ME - MSG Exercised. We examined body weight (BW), retroperitoneal (RET) and epididymal (EPI) white fat pad, gastrocnemius muscle (GAST) and liver weigths (g), "in vivo" lipogenesis rate (LR - m mol 3H2O incorporated into lipid/g. tissue.h.), adipocyte area (AA - mm2), muscular and hepatic glycogen content (mg/100mg), plasma triglyceride, lactate and glucose (mg/dl). Exercise induced a 15% BW reduction in both C and M groups. RET (3.6 ± 0.2) and EPI (3.2 ± 0.2) weights as well as RET LR (5.2 ±1.2) elevated in MS, were reduced in ME (2.1 ± 0.4, 2.0 ± 0.2, 2.2 ± 0.5, respectively). EPI LR was not affected by either MSG treatment or exercise. The liver LR was similar between CS (3.9 ± 0.3) and CE (4.3 ± 0.6), but it was increased in MS (8.4 ± 1.0). Exercise induced a 40% liver LR reduction in ME (4.9 ± 1.1). Exercise increased significantly gastrocnemius muscle glycogen content in CE (0.7 ± 0.05) and ME (0.7 ± 0.05) in relation to CS (0.5 ± 0.03) and MS (0.5 ± 0.04). The plasma triglycerides (103.5 ± 2.1), glucose (155.4 ± 10.8), and lactate levels (0.8 ± 0.07) of MS were normalized by exercise in ME (90.5 ± 2.6, 114.7 ± 14.8, 0.6 ± 0.04, respectively). In MS, AA of RET (23571 ± 735) and EPI (3366 ± 118) were significantly higher than those in CS (7591 ± 217, 2141 ± 65, respectively). Exercise caused a reduction of AA in ME RET (10655 ± 346) and EPI (2357 ± 77). The data showed that exercise was able to normalize all parameters studied which reached levels similar to those of control sedentary rats. These results suggest that continuous exercise can prevent the development of the obesity induced by MSG
