The potential for synthesis of
prostaglandin E2 (
PGE2) in cerebrum (CC), cerebellum (CM), mid-brain (MB) and brain stem (BS) was measured in 1 and 15 month old male F344 rats fed diets containing 0, 30, or 200 IU
vitamin E (-E, E, +E, respectively) and 0.0, 0.1, or 0.2 ppm
selenium (-Se, Se, +Se, respectively) for 8 or 20 weeks. Regardless of dietary treatments, the rank order of
PGE2 synthesis was CC greater than CM greater than BS = MB in the young rats; CC greater than MB greater than BS = CM in the old rats; and CC greater than MB greater than BS greater than CM in the aged rats.
PGE2 synthesis in all brain regions were significantly influenced by dietary treatments except CC. -E diets increased and +E diets decreased
PGE2 production. Young rats were most susceptible to
PGE2 alteration by
vitamin E deficiency while old rats responded most markedly to supplementation. All brain regions showed decreases in their capacity to synthesize
PGE2 with age, except MB where the opposite effect was seen. Dietary Se treatment had a minimal role in
PGE2 synthesis in gross anatomical regions of brain. The degree to which
PGE2 synthesis is affected is more dependent on dietary
vitamin E level and tissue
alpha-tocopherol content than on Se. CM and BS of aged rats appear to require more
alpha-tocopherol to maintain steady state levels than other areas, thus the synthesis of
PGE2 in these regions could be highly susceptible to alterations in dietary
vitamin E.