ENDOGENOUS SYNTHESIS OF GALACTOSE IN NORMAL MEN AND PATIENTS WITH HEREDITARY GALACTOSEMIA

Despite restricted ingestion of lactose, patients with galactose-1-pho sphate uridyltransferase deficiency have raised concentrations of gala ctose metabolites in blood and urine. Endogenous production of galacto se may underlie this phenomenon. Using isotopically labelled galactose in a continuous intravenous infusion, we employed the steady-state fl ux method to calculate endogenous galactose production rate in three n ormal men and three patients with classic galactosaemia. We found that galactosaemic patients and normal subjects synthesise gram quantities of galactose per day. The rate of synthesis ranged from 0.53-1.05 mg/ kg per h. Endogenous production of galactose may be an important facto r in the pathogenesis of the complications of the brain and ovary, and could explain the persistent elevation of galactose metabolites in pa tients despite dietary restriction of galactose.