| Abstract: | Objective: To investigate the effects of follistatin(rhFS-288) on biosynthesis andsecretion of testosterone in rat Leydig cell in vitro.Methods: Leydig cells were isolated from Wistar rat testes by a discontinuous Per-coll gradient procedure. Purified cells were incubated in 24-well plate(105 cell/ml/well)and maintained for 24 h in a CO2 incubator. rhFS-288 and Ca2+ were added to the wellsindependently or jointly in both baseline (without hCG) and stimulation condition (1.0IU/ml of hCG) to observe the change of testosterone concentration in the media.Results: rhFS-288 showed a dose-dependent inhibiting effect on testosterone releasein baseline and stimulating condition. Ca2+ presented inhibitory effect either. Whereas,escape phenomenon emerged while Ca2+ concentration reached to 100 mmol/L. A com-bination of rhFS-288 with Ca2+ displayed a dose-dependent inhibition on testosterone se-cretion.Conclusion: rhFS-288 inhibits testosterone secretion in a dose-dependent manner.Calcium is thought to be the second messenger of FS action. The mechanism of escapephenomenon during high dose of Ca2+ along is unknown. |
