[Induction of tyrosine aminotransferase (EC 2.5.1.5) by nicotinamide in rat liver (author's transl)].

In intact rats nicotinamide induces an increase of tyrosine aminotransferase depending on the dose of nicotinamide. In adrenalectomized rats an increase of tyrosine aminotransferase activity is only found up to a dose of 250 mg/kg nicotinamide. The combination of nicotinamide with L-methionine and/or cortisone acetate does not cause a significant increase of the enzyme activity, which, however, can be seen in the presence of L-tyrosine.