2. Materials and methods
2.1. Animal
Male Wistar rats (180–200 g) were obtained from National Laboratory Animal Center, Mahidol University, Salaya, Nakornpathom. They were housed in animal care facility at the Faculty of Pharmaceutical Sciences, Chulalongkorn University, under controlled environmental conditions (room temperature 25 ± 1 °C with 12-h light:12-h dark cycle, relative humidity of approximately 60%) with free standard rat pellets and tap water. Rats were acclimatized for 3 days before experimentation.