During the experiments following drugs were used; morphine HCl (Sigma, USA) at 0.1, 1, 5 and 10 mg/kg, mecamylamine HCl (Merck Sharp&Dohme) at 1 and 3mg/kg, coniine (Sigma, USA) at 10 and 20 mg/kg doses and acetic acid (Merck, USA).
The drugs were dissolved in saline and were administered intraperitoneally in a volume of 0.1 ml/10 g of body weight. Dilutions from stock solution were performed on a daily basis