2.3. Pharmacokinetic study in rats

Ten to twelve-week-old adult male rats weighing 200–250 gm were obtained from the Experimental Animal Care Center, College of Pharmacy, King Saud University. The animals were acclimated in our laboratory for 2 days under standard humidity, temperature (25 ± 2 °C), and light (12 h light/12 h dark). Rats were fed with a standard pellet diet and had free access to water. After 2 days of acclimation, the rats were divided into 2 groups each consisting of 4 rats. Rats of one group were injected intraperitoneally with combination of FTD and TIP standard solutions while the rats of the control group were injected with saline solution. The dose is 35 mg/m² at ratio of 1:0.5 (FTD: TIP) which was converted to 5.6 mg/kg according to the Meeh′s formula (Gouma et al., 2012). Orbital blood samples were withdrawn from control and treated groups at 0.5, 1, 2, 4, 6, 8, 10, 12, and 24 hr after injection, and were transferred into heparin tube. Plasma were separated from blood by centrifugation at 3000 rpm at 4 °C for 10 min, and then stored at −2°C. A quantity of 50 μl of plasma sample was transferred to 1.5 ml Eppendorf tube, and was spiked and analyzed as described above. All animal procedures obeyed the standards set forth in the guidelines for care and use of experimental animals by the Committee for the Purpose of Control and Supervision of Experiments on Animals (CPCSEA, 2003). The study protocol was approved by the Animal Ethics Committee of Pharmacology Department, College of Pharmacy, King Saud University (Ref. No. KSU-SE-18-18).