Myocardial non-esterified fatty acids during normoxia and ischemia in Langendorff and working rat hearts.

In isolated perfused rat hearts, the tissue levels of non-esterified fatty acids (NEFA) decreased during normoxic perfusion for 60 min in the working heart but not in the Langendorff heart. The levels of both saturated and unsaturated NEFA increased during ischemia for 20 min in the working heart but not in the Langendorff heart, although unsaturated NEFA increased in the Langendorff heart when the ischemic period was 40 min. Arachidonic and linoleic acids were the NEFA that accumulated most prominently.