Anti-androgen flutamide affects gonadal development and reproduction in medaka (Oryzias latipes).
The effects of an anti-androgenic chemical on the reproduction of medaka (Oryzias latipes) were examined. Six mating pairs of medaka were exposed to flutamide (FLU) at measured concentrations of 0.101, 0.202, 0.397, 0.787, or 1.56 mg/L for 3 weeks. During the exposure period, one female died in the 1.56-mg/L treatment group, but no lesions or pathological abnormalities were observed. The fecundity and fertility of paired medaka were significantly decreased at 1.56 mg/L compared with those of the controls. Histological examination showed intersex gonads (testis-ova) in males exposed to FLU at 0.202, 0.397, and 0.787 mg/L. However, concentrations of hepatic vitellogenin (Vtg) in both sexes were not statistically different from those in the controls. These results demonstrate that FLU affected gonadal development in male medaka and reproductive capacity in paired medaka. This is the first report of testis-ova in male medaka exposed to FLU.
Kang
Ik Joon
IJ
Division of Bioresource and Bioenvironmental Sciences, Kyushu University Graduate School, Hakozaki 6-10-1, Higashi-ku, Fukuoka 812-8581, Japan.
Hano
Takeshi
T
Oshima
Yuji
Y
Yokota
Hirofumi
H
Tsuruda
Yukinari
Y
Shimasaki
Yohei
Y
Honjo
Tsuneo
T
D000726:Androgen Antagonists / Q000633:toxicity*; D000818:Animals; D004305:Dose-Response Relationship, Drug; D005260:Female; D005485:Flutamide / Q000633:toxicity*; D006066:Gonads / Q000187:drug effects* / Q000254:growth & development; D008099:Liver / Q000737:chemistry; D008297:Male; D009990:Oryzias / Q000502:physiology*; D012098:Reproduction / Q000187:drug effects*; D014819:Vitellogenins / Q000032:analysis
D000726:Androgen Antagonists; D014819:Vitellogenins; D005485:Flutamide