2.5 Drugs

Racemic α-pyrrolidinopentiophenone HCl (α-PVP) was obtained from Cayman Chemical Company (Ann Arbor, MI, USA). Racemic 3,4-methylenedioxypyrovalerone HCl (MDPV) was obtained from Fox Chase Chemical Diversity Center (Doylestown, PA, USA). All drugs were expressed as the salt and dissolved in physiological saline (0.9%). For locomotor and temperature studies, rats were administered 0.9% saline vehicle, α-PVP (0.25, 0.5, 1.0 and 5.0 mg/kg) or MDPV (0.25, 0.5, 1.0 and 5.0 mg/kg) via intraperitoneal (i.p.) injection with an injection volume of 1 ml/kg body weight. Dosing order was counterbalanced within each group with 3–6-day intervals between sessions necessitating a 4 week interval for each drug series.