IC50: N/A SKF 10047 hydrochloride is a prototypical σ1 receptor agonist. Behaviorally active in animal models of memory and stress. It has been fully demonstrated that σ binding sites are distinct from phencyclidine binding sites on the NMDA receptor-ion channel complex, which has investigated extensively the functional role of σ receptors in the central nervous system . In vitro: The effects of the stereoisomers of N-allylnormetazocine (SKF-10,047) were compared in rats on the hippocampal cholinergic functions. A putative σ1 receptor agonist, (+)-SKF-10,047, increased hippocampal extracellular acetylcholine level as well as anti-amnesic effect against scopolamine-induced memory dysfunctions in rats. Haloperidol, a putative σ1 receptor antagonist reversed these phenomena which were not produced by (-)-SKF-10,047. Such stereoselectivity and antagonism imply σ1 receptors involved in these (+)-SKF-10,047-stimulated hippocampal cholinergic functions . In vivo: (+)-SKF-10,047 and dextromethorphan, being co-administered with phenytoin (10 mg/kg, an anticonvulsant drug), decreased conditioned fear stress with low doses (4 and 20 mg/kg, respectively). The effects were antagonized by the σ receptor antagonists, NE-100 and BMY-14802. Furthermore, the effects of (+)-SKF-10,047 or dextromethorphan plus phenytoin were inhibited by the dopamine D1 receptor antagonist (SCH 23390) and the dopamine D2 receptor antagonist ((-)-sulpiride), and they were also decreased by 6-hydroxydopamine-induced lesions of dopaminergic neurons. The ameliorating effects of (+)-SKF-10,047 and dextromethorphan on condition of fear stress using high doses (5 and 30 mg/kg, respectively) were also inhibited by both the dopamine receptor antagonists . Clinical trial: So far, no clinical study has been conducted.