Induction of tyrosine aminotransferase in galactosamine hepatitis.

We have induced acute hepatitis in rats with the amino sugar Galactosamine by i.p. injection. The development of the disease was controlled by measurements of several metabolites and enzymes in serum, and light and electronic microscopy. Tyrosine transaminase was induced by i.p. injection of Cortisol, that increases ten times enzyme activity in liver parenchyma of normal rats. This inductive phenomenon cannot be observed in animals with galactosamine hepatitis. We discuss the probable mechanism and their relationship with some forms of viral hepatitis in human beings.