After obtaining the approval of the Institutional Review Board of our university, all experiments were carried out in accordance with the Guidelines for the Animal Care and use ethics committee of the Baqiyatallah University of medical sciences. Thirty-six adult male Wistar rats weighing from 190 to 220 g were maintained under standard laboratory conditions. Animals were housed in an environment of 21 ± 2℃ with a relative humidity of 50 to 10% and a 12-hr light–dark cycle. Food and water were always available.