Effect of Prostaglandin E₂ on Adenylate Cyclase Activity in Isolated Glomeruli and Tubules during Postnatal Maturation of Rat Renal Cortex

Abstract

To examine the effect of prostaglandins on adenylate cyclase during the postnatal maturation of kidney, the prostaglandin E₂ (PGE₂) responsiveness of adenylate cyclase in the absence and presence of exogenous GTP was investigated in glomeruli and tubules isolated from renal cortex of 14-, 21- and 30-day-old rats. In the absence of GTP, the adenylate cyclase response to PGE₂ in glomeruli of 14-day-old rats was about fourfold higher than that in 21- and 30-day-old rats. In the tubules there was an about 30–35% decrease in the enzyme response to the prostaglandin between 14 and 21 days as well as between 21 and 30 days. When GTP was present, the PGE₂ responsiveness of adenylate cyclase was of the same order of magnitude in glomeruli at 14 and 21 days and lower at 30 days. Under the same conditions, no significant changes were observed in the cortical tubules throughout the period studied. Thus association of PGE₂ plus GTP suggests that during the postnatal maturation of rat kidney, the response of adenylate cyclase to PGE₂ remains unchanged in cortical tubules and slightly decreases in glomeruli.