Estrogen-induced inhibition of spermatogenesis in zebrafish is largely reversed by androgen.

The hormonal regulation of spermatogenesis involves both gonadotropins and steroid hormones. Long-term exposure of adult zebrafish to estrogen impaired spermatogenesis associated with an androgen insufficiency, possibly induced by inhibiting gonadotropin release. Using this experimental model, we investigated if androgen treatment could enhance spermatogenesis, while maintaining the inhibition of gonadotropin release through continued estrogen exposure.

Isolation of mast cells from the peritoneal exudate of the teleost fish gilthead sea bream (Sparus aurata L.).

Inflammation is the first response of animals to infection or tissue damage. Sparus aurata (Perciformes) was the first fish species shown to possess histamine-containing mast cells at mucosal tissues. We report a separation protocol for obtaining highly enriched (over 95% purity) preparations of fish mast cells in high numbers (5-20 million mast cells per fish).