Objective    To study the toxic effect of flutamide (Flu) on testis with DNA chip.     Methods    Flu was injected subcutaneously at doses of 6.25 mg·kg

-1

·d

-1

to 25 F0 rats from gestation day (GD) 12 to 17

and the 25 rats of control group received same doses of normal saline. All 50 pregnant SD rats were sacrificed on GD 20.The cDNA were extracted respectively from fetal testis

then reversely transcribed to cDNA and labeled with cy5 and cy3 fluorescence. Subsequently

cDNA probes were hybridized to the Mouse40S cDNA microarray and fluorescence signals were analyzed. Testosterone level was determined by enzyme-linked immunosorbent assay (ELISA).     Results    Compared with control，a total of 31 identified gene was found to be expressed

differently

including 14 down-regulated and 17 up-regulated. Among them

5 down-regulated and 10 up-regulated genes were unknown in Genbank. ELISA indicated that testosterone levels were decreased in Flu toxic group.     Conclusion    Flu treatment to F0 pregnant rats can damage apparently to the reproductive development of embryonic period male SD rats. The obtained differential genes may provide reference for the molecular mechanism of reproductive development.