Retinol deficient diet decreases binding activity of testicular fatty acid-binding protein

Fatty acid-binding protein (FABP) activity was determined in livers and testes of retinol sufficient, retinol deficient, and also in a group of retinol deficient rats, which were refed 100 micrograms of retinyl acetate for four hours. [14C]palmitoyl CoA binding assay was used to estimate the binding activity of FABP. In retinol sufficient and retinol deficient groups, liver FABP bound 431 and 446 pmol [14C]palmitoyl CoA/mg cytosolic protein respectively. In contrast, testicular FABP bound 254 and 139 pmol [14C]palmitoyl CoA/mg cytosolic protein in retinol sufficient and deficient groups. Retinol deficiency caused a tissue specific change in testicular FABP and not in liver FABP. Liver and testicular FABP's remained unchanged after four hour refeeding of retinol to retinol deficient rats.