MARKED REDUCTION OF ACYL-COA SYNTHETASE-ACTIVITY AND MESSENGER-RNA ININTRAABDOMINAL VISCERAL FAT BY PHYSICAL EXERCISE

Several reports have suggested that the reduction of intra-abdominal v isceral fat after physical exercise is more prominent than that of sub cutaneous fat. We compared some parameters in mesenteric and subcutane ous fats between sedentary and exercised rats (treadmill running; 10-2 0 m/min, 60 min/day, 7 days). Tissue weight and cell volume were decre ased in mesenteric fat by the exercise. The exercise reduced activity and mRNA levels of acyl-CoA synthetase (ACS; 67 and 26% of those of th e sedentary group, respectively), mRNA levels of lipoprotein lipase (L PL; 49% of those of the sedentary group), and GLUT-4 (38% of those of the sedentary group) in the mesenteric fat. In contrast, all of these parameters did not change significantly in the subcutaneous fat. Gastr ocnemius muscle was heavier in exercised rats. ACS activity was elevat ed in the gastrocnemius muscle of the exercised rats (137% of those of sedentary group), although mRNA levels of ACS, LPL, and GLUT-4 did no t change in the muscle by the exercise. These observations suggest tha t mesenteric fat may contribute to switching of distribution of plasma energy flux, including lipid and glucose, from fat tissue to muscle i n physical exercise.