Short-Term Radioprotective Effects of WR-2721 on the Rat Parotid Glands

Abstract
The radioprotective capacity of the chemoprotector WR-2721 [S-2-(3-aminopropyl amino)-ethylphosphorothioic acid] was assessed in the rat parotid gland using gland weight and amylase content as the indicators of effect over the 9-day period following X-irradiation with 1.6, 3.2 and 6.4 kR of acute X-rays. The decline and recovery of weights and amylase content were measured and compared in animals which had and had not received WR-2721 just prior to irradiation. Analysis of the dose-response curves for the WR-2721 protected vs. nonprotected animals yielded dose modification factors of 2.5 for gland weight, 1.7 for amylase concentration and 1.8 for total gland amylase. WR-2721 was effective in yet another tissue and to a degree consistent with that of other organs and systems.