Expression of insulin-like factor 3 in the testis of flutamide-induced cryptorchidism mice and its significance

Objective: To study the changes in the mRNA expression of insulin-like factor 3( INSL-3) in the testis of mouse models of flutamide-induced cryptorchidism. Methods: We randomized pregnant BALB / c mice to groups A( control),B,C,D and E to receive continuous gavage of flutamide at 0,150,300,500 and 700 mg / kg body weight,respectively,from gestation day 12 to21. We detected the expression of INSL-3 mRNA in the testis of the neonates by real-time PCR at 4 and 8 postnatal weeks. Results:No cryptorchidism was found in group A; unilateral cryptorchidism was seen in groups B( 10. 0%) and C( 25. 0%); and bilateral cryptorchidism was observed in groups D( 21. 1%) and E( 40. 0%). The expression of INSL-3 mRNA was reduced with the increased dose of flutamide,not significantly changed in groups B and C( P 0. 05) but remarkably decreased in D and E as compared with A( P 0. 05). Conclusion: Administration of flutamide to pregnant mice can induce unilateral cryptorchidism at 150 and 300 mg/kg and bilateral cryptorchidism at 500 and 700 mg / kg in their male offspring,which may be related with its reducing effect on the expression of INSL-3 in the testis of the mice.