The study was carried out to determine the pharmacokinetic parameters after intravenous(iv) and intramuscular(im) administration (10㎎/㎏) in healthy rabbits. The results obtained through the experiments were summarized as follows:
1. Bioassay (Bacillus cereus 11778) was evaluated very useful for the determination of oxytetracycline(OTC) in the rabbit serum and tissues, with the detection limit of 0.12㎍/㎖.
2. The pharmacokinetic profiles of OTC (10㎎/㎏, iv) in rabbits were best described with a two compartment open model (C=29.5e^(-4,3t)±3.6^(-0.2t)), whereas that of OTC (10㎎/㎏, im) showed a one compartment curve fitting.
3. Following iv administration, a rapid distribution phase was predominant [t_½(α):1.43±0.98hr(♂), 0.5±0.1hr(♀)], and then more slow elimination phase ensued [t_½(β):4.52±0.76hr(♂), 7.32±2.52hr(♀)]. Other computer generated pharmacokinetic values were as follows:C1 [67.76±18.59 ㎖/㎏/h(♂), 76.03±2.98 ㎖/㎏/h (♀)] Vd [257.74±180.47 ㎖/㎏ (♂), 92.33±23.62 (♀)] AUC [25.6±4.44 ㎎h/L (♂), 39.6±12.13 ㎎h/1 (♀)]. There were no statistical significance between. both sexes for all the parameters at the confidence level of 95%.
4. After im administaration, the absorption from the injection sites was very rapid [ Ka:0.18±10.03 h^(-1) (♂), 0.24±0.02 h^(-1) (♀)] followed by a monoexponential elimination fashion. The time to peak blood level (Tmax) were calculated 1.64±0.15 hr and 1.34±0.24 hr, in the male and female, respectively. The peak levels (Cmax) at the cornspcmding time were 1.b9±0.23㎍/㎖ (♂) and 2.08±0.16㎍/㎖ (♀), with no statistical differences (p>0.05).
|