THE EFFECTS OF INDOMETHACIN ON ERYTHROPOIETIN PRODUCTION IN DOGS FOLLOWING RENAL ARTERY CONSTRICTION. I. THE POSSIBLE ROLE OF PROSTAGLANDINS IN THE GENERATION OF ERYTHROPOIETIN BY THE KIDNEY

¹ Department of Pharmacology, Tulane University School of Medicine, New Orleans, Louisiana

In an attempt to clarify the role of prostaglandins in the generation of erythropoietin (ESF) by the kidney, ESF titers were compared in the plasma of dogs following renal artery (RA) constriction with and without prior treatment with indomethacin. In that indomethacin is an inhibitor of prostaglandin synthesis, the role of renal prostaglandins in ESF production by the kidney following RA constriction could be assessed. Plasma from dogs was removed for ESF assay before and after 24 hours of RA constriction (constricted to 30% of control value) in control dogs and dogs treated with indomethacin. Indomethacin was administered orally (5.0 mg/kg) 18 hours and 1 hour before the RA constriction. A third dose of indomethacin was administered 6 hours after RA constriction. It was found that RA constriction produced a significant (P > .01) increase in ESF titers in control dogs after 24 hours. However, dogs treated with indomethacin and RA constriction did not show a significant increase in plasma ESF levels. These data suggest that renal prostaglandins are involved in the generation of ESF by the kidney following RA constriction and may be the first step in a sequence leading to kidney production of ESF.