Tissue Utilization of Fatty Acids

Fatty acid oxidation requires adequate amounts of NAD and FAD. Oxidation of NADH and FADH2 occurs in mitochondria via electron transport and the use of molecular oxygen. However, the electron transport chain can only function if ADP is present, so that fatty acid breakdown occurs at the rate necessary to maintain cellular levels of ATP which decrease if metabolic or other work is performed. Tight coupling of electron transport to oxidative phosphorylation (Chapter 14) is of considerable importance in fuel economy. Without it, fatty acids would be utilized in an unproductive manner. In the liver, fatty acids in excess of requirements are converted to triacylglycerols and secreted as VLDLs. 

Regulation of fatty acid oxidation in cardiac muscle. 

---