Comparison of Behavioral and Radioprotective Effects of WR-2721 and WR-3689

摘要

The behavioral effects of the radioprotectant agents ethiofos, S-2-(3-aminopropylamino)ethylphosphorothioic acid (WR-2721) and S-2-(3-methylaminopropyl)aminoethylphosphorothioic acid (WR-2721) and S-2-(3-methylaminopropyl)aminoethylphosphorothioic acid (WR-3689) were evaluated in rats trained to respond under a multiple fixed-interval 120-s, fixed-ratio 50-response (mult FI FR) schedule of milk reinforcement. Performance of groups that received pretreatment with the 180-mg/kg dose of either drug or the 56-mg/kg dose of WR-3689 was maintained at significantly higher levels than saline-treated controls on days 4-5 after exposure to 10 Gy; however, even at these higher levels of performance response rates remained below 50% of preirradiation control levels. Subsequently, 56 and 180 mg/kg WR-3689 and 180 mg/kg WR-2721 were found to provide protection against the lethal consequences of the 10-Gy exposure. Thus, neither WR-2721 nor WR-3689 afforded any significant short-term protection against radiation-induced performance decrements when these drugs were administered at either behaviorally ineffective or behaviorally disruptive doses. Rather, the beneficial effects of these drugs paralleled their ability to antagonize radiation-induced lethality.