ARACHIDONATE TRANSPORT THROUGH THE BLOOD-RETINA AND BLOOD-BRAIN-BARRIER OF THE RAT DURING AGING

The permeability-surface area product (PS) of [1-C-14]arachidonate at the blood-retina (BRB) and blood-brain barrier (BBB) was determined af ter short carotid perfusion in Wistar rats at 4, 12 and 28 months of a ge. For the visual system structures, parietal and frontal cortex, str iatum, hypothalamus, hippocampus and olfactory bulb there was no signi ficant difference among mean PSs in any age group. Our results indicat e that: (1) arachidonate is able to cross at relevant rate BRB and BBB ; (2) in all brain regions except retina, optic tract and hippocampus, blood barriers have a transport capacity for arachidonate significant ly higher than that for docosahexaenoate and palmitate as well; (3) ag ing does not affect influx into retina and other structures of rat cen tral nervous system of the arachidonate, a metabolic substrate rapidly incorporated into microcapillary and brain lipids, and for which simp le diffusion transport across the BRB and BBB may be postulated.