Adaptation of the rat liver tyrosine-α-ketoglutarate transaminase

Adaptive increase of the tyrosine-α-ketoglutarate transaminase occurred in the livers of rats following injections of tyrosine or of hydrocortisone. The increases were as great as 10-fold and occurred in 5 hours. Analysis showed that hydrocortisone itself was a sufficient inducing stimulus. Tyrosine was an effective inducing stimulus only if the adrenal glands or hydrocortisone also were present.