PJ34 hydrochloride is an inhibitor of PARP1/2 with IC₅₀ of 110 nM and 86 nM, respectively. IC50 & Target: IC50: 110 nM (PARP1), 86 nM (PARP2)^[1] In Vitro: PJ34 inhibits the PARP enzyme activity with an IC₅₀ of 110±1.9 nM. To compare the neuroprotective properties of other PARP inhibitors in PC12 cells, PJ34 is evaluated using by LDH assay. PJ34 treatment also significantly and concentration dependently attenuates cell death at a concentration ranging from 10^-7 to 10^-5 M^[1]. In Vivo: To compare the potency and efficacy with other PARP inhibitors, PJ34 is evaluated at the doses of 3.2 and 10 mg/kg, respectively. PJ34 at the dose of 3.2 mg/kg significantly reduces cortical damage by 33%; however, 10 mg/kg dosing shows reversed effect (17% reduction)^[1]. PJ34 (25 mg/kg) reduces the levels of TNF-α mRNA in ischemic animals by 70% and these values in treated mice do not differ from that of sham or naive animals. Treatment of ischemic mice with PJ34 reduces the level of E-selectin mRNA by 81% and that of ICAM-1 mRNA by 54%, compared to vehicle-treated ischemic mice^[2].