Rates of protein synthesis and degradation in Gunn rat cerebellum with bilirubin-induced cerebellar hypoplasia.

The rates of protein synthesis and degradation, and the endogenous leucine content on days 13 and 30, were examined in the cerebellum of homozygous Gunn rats with cerebellar hypoplasia and compared with those of heterozygotes. The rate of protein synthesis based on milligrams of protein was significantly lower on day 30 and the degradation rate was about ten times faster between days 13 and 18. Furthermore, leucine concentration was about 1.7 times higher on day 13. The present results suggest that the lowered protein concentration previously observed in the cerebellum of homozygous Gunn rats is ascribed to the increased rate of protein degradation on day 13, and to the decreased rate of protein synthesis on day 30.