FLUX CONTROL EXERTED BY OVERT CARNITINE PALMITOYLTRANSFERASE OVER PALMITOYL-COA OXIDATION AND KETOGENESIS IS LOWER IN SUCKLING THAN IN ADULT-RATS

We examined the potential of overt carnitine palmitoyltransferase (CPT I) to control the hepatic catabolism of palmitoyl-CoA in suckling and adult rats, using a conceptually simplified model of fatty acid oxida tion and ketogenesis, By applying top-down control analysis, we quanti fied the control exerted by CPT I over total carbon flux from palmitoy l-CoA to ketone bodies and carbon dioxide, Our results show that in bo th suckling and adult rat, CPT I exerts very significant control over the pathways under investigation. However, under the sets of condition s we studied, less control is exerted by CPT I over total carbon flux in mitochondria isolated from suckling rats than in those isolated fro m adult rats. Furthermore the flux control coefficient of CPT I change s with malonyl-CoA concentration and ATP turnover rate.