Pyruvate dehydrogenase activity in the liver, brain and adipose-tissue of lipid-deprived developing rats. Effect of minute amounts of polyunsaturated fatty acids.

Unlabelled: The present experiment was carried out using the following diets: FF, fat-free, and LP in same diet with 0.7% sunflower oil - given to the progeny of females kept on the FF diet since the mating. after 10 mM Mg2+ activation of the PDH phosphatase, and rate of [1-14C[ pyruvate decarboxylation into acetyl-CoA ester units was determined in the liver, brain and adipose-tissue of the pair-fed developing rats.

Results: In the male progeny, pyruvate dehydrogenase (PDH) activity was higher (61%) in the LP group livers than in the FF group livers, at the end of the 13 week experiment. Such a difference was not observed in the two group brains up to the 91 days postweaning, but was even larger (94%) between adipose-tissues of the LP and FF groups. In the female progeny kept 12 weeks on the diets, PDH activity in the LP group tissues was also higher than in the FF group tissues: 63% in the liver, 43% in adipose-tissues, and less than 10% in the brain. Therefore, a minute amount of lipids high in linoleic acid appeared to increase PDH activity, and especially in the liver and adipose-tissues of animals kept on a strictly fat-free diet. This stimulation of the PDH activity seems closely related to the phospholipid rehabilitation in the tissues (decrease in the trienoic, tetraenoic acid ratio values).