Anterior pituitary halves from adult male rats were incubated at 37°C in medium 199 in an atmosphere of 95% O2, 5% CO2 for 30 min. Following preincubation, the pituitaries were transferred to either a control medium or a medium containing prostaglandins (7.1 x 10-6M/3.9 x 10-5M) or N6, O2' dibutyryl cyclic AMP (1 to 10 millimol). Following short periods of incubation (2 to 15 min), the pituitary halves were frozen and analyzed for glycogen content, glycogen phosphorylase activity, and cyclic AMP content. Prostaglandins E1 and F2α caused a significant decrease of pituitary glycogen, an activation of glycogen phosphorylase activity, and a marked increase of pituitary cyclic AMP content. Dibutyryl cyclic AMP additions in the presence of theophylline caused a similar activation of pituitary glycogen phosphorylase and a decrease of pituitary glycogen. These effects suggest that prostaglandins play a role in pituitary hormone release through the intermediate action of the cyclic AMP glycogen phosphorylase cascade system.
All Science Journal Classification (ASJC) codes
- Reproductive Medicine
- Obstetrics and Gynecology