Agonists for Radioprotective Effects

DmPGE₂, the EP1,3 dual agonist 17-phenyl trinor PGE₂, the EP2 selective agonist Butaprost (free acid), and the selective EP4 agonist L-902,688, were purchased from Cayman Chemical (Ann Arbor, MI), and were used as described elsewhere (24 (link), 25 (link)). DmPGE₂, and Butaprost in MeAc and L-902,688 in MeOH were evaporated under a stream of N₂ and reconstituted in absolute EtOH. Crystalline 17-phenyl trinor PGE₂ was solubilized in absolute EtOH. All compounds were diluted in phosphate buffered saline (PBS) for injection. DmPGE₂ was injected as a single subcutaneous (s.c.) dose of 35 μg (containing 1.75% EtOH) or two doses of 20 μg (containing 1% EtOH) per mouse at different times relative to irradiation as indicated. The range of doses of dmPGE₂ as a function of all mice used was 1.73 mg/kg for pediatric, 1.6 mg/kg for young adult, and 0.91 mg/kg for geriatric mice, a <2-fold variation among all sexes and ages of mice. EP receptor agonists were injected 30 min prior to TBI as a single s.c. dose of 35 μg (containing 1.75% EtOH) or 10 μg (containing 0.5% EtOH) per mouse. All compounds were injected in a volume of 200 μl per mouse. In all cases, vehicle injections contained equivalent EtOH concentrations.