Comparison of the methods for in vivo FSH bioassay in pharmacopoeia of various countries

Objective: To sort out and compare the follicle-stimulating hormone( FSH) bioassay methods in different national pharmacopoeia based on a large number of long-term experimental data. Methods: Various batches of products of rhFSH,u-FSH,u-FSH-HP and Co rhFSH-rhLH at home and abroad were evaluated by in vivo FSH bioassay method optimized in Chinese pharmacopeia 2010( ChP 2010) and were compared with the method in Ep 7. 0 and the USP 35-NF 30 for FSH in aspects of the number of animals,rat body weight,HCG levels in solvent,FSH dose ranges,response values,etc. Results: The average deviation rate was 2. 3% between each group of eight animals in ChP 2010 and each group of five animals in EP 7. 0 and the USP 35-NF 30; the average confidence limit rate was from 21. 2% to 28. 7%,all in the allowed error range of bioassay. In ChP,female rats being 19-23 d old with body weights ranging 36-50 g had poorer experimental sensitivity and their weights were lower. The ovarian weight gain in 36-40 g rats was significantly smaller than that in 40-50 g rats in blank group( p 0. 05). HCG levels were also lower in solvents; FSH dose ranges were similar to EP 7. 0 and USP 35-NF 30. In contrast to EP 7. 0 and USP 35-NF 30 in which the organ coefficient was taken as the response value,the weight of the ovaries was used as the response value in ChP 2010,but there was no difference between those measurement results significantly. Conclusion: A total of five rats in each group can meet the bioassay requirement of reduction( the 3R principle). It is the best method for FSH bioassay that the rat body weight should be 40-60 g( the difference between the heaviest and the lightest rat is not more than 10 g) on 21-23 days after birth; HCG levels in solvents should be increased to 25-30 IU ·mL-1. ChP 2010 for FSH bioassay should be optimized.