Repinotan

Repinotan (BAY x 3702 free base) is a potent, selective, brain-penetrant and orally active 5-HT1A receptor agonist, with K_i values of 0.19 nM (calf hippocampus), 0.25 nM (rat and human cortex), and 0.59 nM (rat hippocampus). Repinotan has a weak affinity for other related receptors. Repinotan has pronounced neuroprotective effects^[1]. In Vitro: Repinotan binds with lower affinity to 5-HT7 (K_i = 6 nM), α1- and α2 adrenergic (K_i = 6 nM and 7 nM, respectively), 5-HT1D (36 nM), dopamine D2 and D4 (48 nM and 91 nM, respectively), σ sites (176 nM) and 5-HT2C (310 nM) receptors^[1].
Exposure to repinotan protects rat cortical and hippocampal neurons in cultures from apoptosis induced by 25 nM Staurosporine. After Staurosporine-induced apoptosis, Repinotan, at 50 pM to 1 μM, reduces the release of lactate dehydrogenase, DNA fragmentation, and apoptotic body formation in a concentration-dependent manner^[1]. In Vivo: Repinotan (1-100 μg/kg) causes strong, dose-dependent infarct reductions in permanent middle cerebral artery occlusion, transient middle cerebral artery occlusion, and traumatic brain injury paradigms^[1].
The half-life of Repinotan in plasma is relatively short (t1/2 = 0.6 h in rat; 0.4 h in rhesus monkeys), and Repinotan is extensively metabolized^[1].