Role of prolactin on neural and glial cellular enzymes involved in carbohydrate metabolism. I. Studies on immature male bonnet monkeys.

The influence of prolactin (Prl) and bromocriptine on the specific activities of neural and glial cellular enzymes involved in carbohydrate metabolism in cerebral cortex, hypothalamus, cerebellum and pons-medulla was studied. Both Prl and bromocriptine stimulated the activity of hexokinase (HK) in the neural as well as in the glial cells. While Prl increased the activity of phosphofructokinase (PFK), glyceraldehyde-3-phosphate dehydrogenase (G-3-PDH) and pyruvate kinase (PK) in the neural cells, it decreased the same in the glial cells. On the other hand, bromocriptine elevated the activity of all these enzymes in the neural cells without any effect on the glial cells. The activities of neural cellular glucose-6-phosphate dehydrogenase (G-6-PDH) and 6-phosphogluconate dehydrogenase (6-PGDH) were inhibited by Prl, whereas bromocriptine increased the same. The activities of these enzymes in the glial cells were enhanced by both Prl and bromocriptine. Thus, the present study suggests that Prl has a differential effect on the activities of enzymes involved in Embden-Meyerhoff pathway (EMP) and hexosemonophosphate shunt (HMP) in the neural and glial cells of immature male bonnet monkeys.