Renal function and renal venous prostaglandin concentrations during different stages of experimental renal hypertension in the rat.

Renal hypertension was produced in rats and the changes in renal function, renal venous prostaglandin E2 and F2alpha concentrations and secretion rates were studied at various times. Renal plasma flow transiently fell in the ischaemic kidney 2 weeks after clamping, whilst that of the other kidney did not change. Glomerular filtration rate remained constant in both kidneys throughout the entire study. Prostaglandins E2 and F2alpha concentrations rose in the venous plasma from the ischaemic kidney, but did not change in the other kidney and appeared to be inversely related to renal plasma flow. Calculated secretion rate of both prostaglandins fell in the ischaemic kidney and did not change in the other kidney. Clamping the second kidney, two weeks after the first, caused a further elevation in blood pressure, a fall in renal plasma flow and a fall in prostaglandin secretion rate in both kidneys. The implications of these prostaglandin changes are discussed.