Slices of testes from normal rats and rats fed diets deficient in essential fatty acids (EFA) were incubated with [1-14C]acetate, [7α-3H]cholesterol and [4-14C]progesterone as substrates. Incorporation of activity in testosterone and androstenedione was measured.
With [1-14C]acetate and [7α-3H]cholesterol as substrates there was an approximate doubling in the yield of testosterone and androstenedione in the testes of EFA-deficient rats, but with [4-14C]progesterone as substrate the differences between groups were not marked. It is postulated that increased biosynthesis of androgens (from acetate and cholesterol substrates) in EFA-deficient animals is perhaps due to structural changes in the mitochondrial wall causing increased permeability of the substrate to the mitochondrial enzymes. No change in the yield of androgens with [4- 14C]progesterone as precursor is perhaps due to non-involvement of mitochondria for synthesis of progesterone→androgens in the rat testis.