[Effects of prostaglandin F 2 alpha on the activity of NADP-dependent dehydrogenases].

The effects of prostaglandin F2 alpha (0,004--0,4 mg per 100 g) on the activity of NADP-dependent dehydrogenases from rat liver and uterus were studied. After 4 hrs following F2 alpha injection the activities of glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase was found to increase 4,3- and 1,2-fold in the liver and 5- and 1,6-fold in the uterus, respectively. The content of glucose in the blood remained practically unchanged. No correlation between the amount of F2 alpha and the activities of the pentose phosphate pathway dehydrogenases was observed. The effect of F2 alpha on the dehydrogenases from rat uterus (but not liver) depended on the phase of the sexual cycle and reached its maximum in the period of the secretory activity (estrus). The administration of F2 alpha in combination with alpha- and beta-adrenergic blockers (phentolamine or propranolol) did not only enhance but also potentiated their stimulating effects on the activities of the dehydrogenases. F2 alpha shifted the ratio of reduced and oxidized forms of pyridine nucleotides in the liver, increasing it by 11,2 and 33,3% for NADPH/NADP+ and NADH/NADP+, respectively. The NADP-dependent isocitrate, malate and glutamate dehydrogenases from rat liver and uterus as well as the non-oxidizing enzymes of the pentose phosphate pathway of carbohydrate metabolism were insensitive to F2 alpha.