The effect of various metabolic conditions inducing an overproduction of ketone bodies in the rat have been studied at the different level of the D-beta-hydroxybutyrate dehydrogenase (BDH) expression: the enzymatic activity and the protein content in isolated mitochondria, and at the translational activity of isolated polysomes. The strongest variations were obtained under a diabete where the BDH expression is largely decreased. Insulin is able to reverse this diabete dramatic effect. The results are in agreement with the absence of direct relationships between the ketone bodies production and the D-beta-hydroxybutyrate dehydrogenase expression but appears to be controlled by insulin at different levels at least at the transcriptional, post translational and catalytic activities.