RAPID ENHANCEMENT OF ACYL-COA SYNTHETASE, LPL, AND GLUT-4 MESSENGER-RNAS IN ADIPOSE-TISSUE OF VMH RATS

Obesity is frequently accompanied by metabolic and cardiovascular comp lications. The accumulation of intra-abdominal visceral fat has been s hown to be more closely related to various complications of obesity th an that of subcutaneous fat. To elucidate the metabolic characteristic s of visceral fat during fat accumulation, we examined the changes of acyl-CoA synthetase (ACS) mRNA abundance and its activity, glucose tra nsporter (GLUT)-4, lipoprotein lipase (LPL), and very-low-density lipo protein (VLDL) receptor mRNA abundances in mesenteric and subcutaneous fat in early stages of ventromedial hypothalamus (VMH)-lesioned rats. ACS activity increased 4.9-fold in the mesenteric fat on the 1st day, remaining unchanged in the subcutaneous fat. ACS, GLUT-4, and LPL mRN A levels were all increased in both fat tissues of VMH rats. The relat ive increase of mRNAs in VMH day 1 was greater in the mesenteric fat, suggesting that mesenteric fat shows rapid response during fat accumul ation. VLDL receptor mRNA levels showed no significant change in eithe r fat tissue. We conclude that ACS, GLUT-4, and LPL may contribute to fat accumulation at the gene expression level from a very early stage during the development of obesity.