Brain ascorbate depletion as a response to stress.

Ascorbate-depleted rainbow trout were fed a single dose of L-1-14C-ascorbic acid, then held in metabolism chambers for four consecutive five-day periods. Tissue samples were analyzed for 14C, ascorbate, and ascorbate-2-sulfate. Brain ascorbate showed a long turnover time following a very slow uptake. The loss of brain ascorbate after five days in metabolism chambers was highly significant (p less than 0.001) when compared with similar dosed fish not chambered. A brain ascorbate pool which does not exchange with the body pool is proposed. Possible mechanisms are discussed and a kinetic model is suggested.