A novel synthetic cathinone, α-pyrrolidinopentiothiophenone (PVT), produces locomotor sensitization in rat: Implications for GSK3β connections in the nucleus accumbens core.

A novel psychoactive substance, α-pyrrolidinopentiothiophenone (α-PVT), is a structural analog to amphetamine. Recently, it has been shown that α-PVT has an abuse potential similar to psychomotor stimulants like cocaine or amphetamine. However, it has not been performed yet to determine whether α-PVT develops behavioral sensitization, a well-known phenomenon for psychomotor stimulants. In the present study, rats were first pre-exposed to either saline or α-PVT (20 mg/kg, IP) with a total of four injections in every 2-3 days of interval. Then, 2-weeks after withdrawal, locomotor activity was measured with a challenge dose (10 mg/kg, IP) of α-PVT and the nucleus accumbens core region was taken out. Similar to psychomotor stimulants, repeated administration of α-PVT produced locomotor sensitization. Further, the phosphorylation levels of GSK3β in the nucleus accumbens core were found to be decreased only in rats with sensitization developed, but not in those with acute or non-sensitized. Correlation analysis revealed that the phosphorylation levels of GSK3β have a strong negative correlation with locomotor activity only in rats with α-PVT pre-exposed, but not in those with its acute injection. These results suggest that a certain level of change in the phosphorylation levels of GSK3β in the nucleus accumbens core may involve in mediating the expression of locomotor sensitization by repeated injection of α-PVT in rats.