Are cytoskeletal components involved in the control of hepatic carnitine palmitoyltransferase I activity?

The present work was undertaken to test whether cytoskeletal components are involved in the control of rat-liver carnitine palmitoyltransferase I (CPT-I) activity by cellular effectors. The microtubule stabilizer taxol abolished the changes in CPT-I activity induced by the effectors tested. Taxol also prevented OA-induced shrinkage of hepatocytes as well as the enhanced release of lactate dehydrogenase from digitonin-permeabilized hepatocytes. On the basis of its relative sensitivity to tautomycin and OA, the modulation of CPT-I activity seemed to involve mostly protein phosphatase 1. These data suggest that the short-term control of hepatic CPT-I by cellular effectors may involve modulation of interactions between CPT-I and cytoskeletal components.