OPC-14523 hydrochloride is an orally active sigma and 5-HT1A receptor agonist, with high affinity for sigma receptors (σ1/2 IC 50 =47/56 nM), the 5-HT1A receptor ( IC 50 =2.3 nM), and the 5-HT transporter ( IC 50 =80 nM). OPC-14523 hydrochloride shows antidepressant-like activity In Vitro OPC-14523 hydrochloride inhibits the in vitro reuptake of 3 H-5-HT (IC 50 =27 nM), but it shows very weak inhibitory activity on 3 H-NE and 3 H-DA reuptake. MCE has not independently confirmed the accuracy of these methods. They are for reference only. In Vivo OPC-14523 hydrochloride (0.3-100 mg/kg; p.o.; daily for 0, 2, 4, 7 days) produces a marked antidepressant-like effect in the forced swimming test (FST) with rats and mice without affecting the general locomotor activity . MCE has not independently confirmed the accuracy of these methods. They are for reference only. Animal Model: Wistar strain of rats (140-245 g) Dosage: 0.3-100 mg/kg Administration: P.o.; daily for 0, 2, 4, 7 days Result: A single doses of 1 mg/kg and higher of OPC-14523 reduced immobility time in the FST with an ED 50 value of 27 mg/kg. The ED 50 value for OPC-14523 on day 7 was 18 mg/kg. Animal Model: ICR strain of mice (25-45 g) Dosage: 0.3-100 mg/kg Administration: P.o.; daily for 0, 2, 4, 7 days Result: A single oral dose of OPC-14523 produced a marked reduction in immobility time during the FST at oral doses of 1 mg/kg and higher, with an ED 50 value of 20 mg/kg. The potency of OPC-14523 in decreasing immobility time was greater after treatment for seven consecutive days, producing an ED50 value of 2 mg/kg. Form:Solid IC50& Target:sigma 1 47 nM (IC 50 ) sigma 2 56 mM (IC 50 ) 5-HT 1A Receptor 2.3 nM (IC 50 )