WR-2721 inhibition of radiation-induced prostaglandin excretion in rats

Pre-irradiation administration of the radioprotectant drug WR-2721 :S-2-(3-aminopropylamino)-ethyl phosphothioic acid] to rats resulted in a significant reduction in radiation-induced increases in excretion rates of prostaglandins (PGE and PGFsub(2α) and thromboxane (TxB2). In animals not irradiated, WR-2721 did not significantly alter these excretion rates. Dramatic reductions in the levels of urinary PGE and TxB2 were observed following exposure to 9.0 Gy of whole-body, unilateral γ-radiation in WR-2721-treated animals, whereas changes in PGFsub(2α) levels were less pronounced. Radiation-induced diuresis was also significantly depressed in animals given WR-2721 before irradiation. Reduced prostaglandin excretion rates may reflect the general radioprotective capacity of the chemoprotector WR-2721 on the release of prostaglandins from radiation-damaged tissue. The decrease in diuresis may be related to the observed prostaglandin decreases. (author)