Metabolism of 4,7,10,13,16,19-docosahexaenoic acid in isolated perfused adult and newborn pig eyes.

We performed open-circuit perfusions of newborn and adult pig eyes to study the age-dependent metabolism of 4,7,10,13,16,19-docosahexaenoic acid (DHA) in this organ. DHA taken up by the perfused eyes was partitioned into glycerolipids, beta-oxidation, and the intracellular nonesterified fatty acid pool. In newborn eyes, DHA was incorporated into structural lipids to a greater extent than in adult eyes. Competition experiments suggest that the adult eye is more selective for DHA than the newborn eye. Finally, pulse-chase data indicate that DHA transport from the circulation across the retinal pigment epithelium and into the retina is more rapid in adult than in newborn eyes. The results are discussed with respect to the rapid accumulation of retinal DHA in early life and the avid retention of this fatty acid by the adult retina.