Studies on pharmacokinetics of recombinant human basic fibroblast growth factor in rabbits by ¹²⁵I radioiodination and enzyme linked immunosorbent assay

Aim: To compare the recombinant human basic fibroblast growth factor (rhbFGF) pharmacokinetic results from ¹²⁵I radioiodination method and enzyme linked immunosorbent assay (ELISA). Method: Establishing ¹²⁵I radioiodination method and ELISA to examine the fate of rhbFGF in rabbits. Result: Pharmacokinetic parameters were calculated by statistical analysis after iv administration of 4, 2 and 1 μg/kg of ¹²⁵I-rhbFGF or rhbFGF in rabbits, with 98.84, 75.15, 71.57 min for t_1/2 and about 5 min for Cltot in radioiodination method, and 17.18, 16.24, 23.92 min for t_1/2 and about 10 min for Cltot in ELISA. The AUCs were linearly correlated to doses in both cases (r_{radioiodination} = 0.9999; r_ELISA = 0.9982. The results from two methods have a correspondence, and significant differences also exist. Conclusion: Labelled rhbFGF presents the different fate in rabbits compared with unlabelled rhbFGF.