6-Ketoprostaglandin E1 stimulation of rat and rabbit renal adenylate cyclase-cyclic AMP systems

6-Ketoprostaglandin E1 effects on rat and rabbit renal adenylate cyclase-cyclic AMP systems were examined. Adenylate cyclase activity was assessed in the 1000 X g fractions prepared from different areas of kidney. 6-Ketoprostaglandin E1 caused a dose-dependent increase in rat cortical and medullary adenylate cyclase activity with 8 x 10(-6) M being the lowest effective concentration. Combinations of maximal stimulatory concentrations of 6-ketoprostaglandin E1 and prostaglandin I2 caused stimulation similar to that seen with either agent alone. In contrast, the combination of either prostaglandin with parathyroid hormone (cortex) or antidiuretic hormone (medulla) resulted in enzyme activity significantly greater than with either agent alone. Similar results were observed in the rabbit. In addition, rabbit cortical and medullary slice cyclic AMP content was increased by 6-ketoprostaglandin E1. Maximal stimulatory effects of 6-ketoprostaglandin E1 on adenylate cyclase activity and cyclic AMP content were similar to prostaglandin I2. Therefore, the similarity in physiologic actions of 6-ketoprostaglandin E1 and prostaglandin I2 may be due to the stimulation of adenylate cyclase by both agents. These prostaglandins and the polypeptide hormones appear to activate different renal adenylate cyclase-cyclic AMP systems.