In vitro action of leptin on gonadotropin secretion in pre-pubertal male chub mackerel

Leptin directly influences gonadotropin (GTH) secretion from female pituitary cells in vitro and is a key signal at the onset of puberty in female chub mackerel (Scomber japonicus). Here, we investigated whether leptin also influences GTH secretion in male chub mackerel. The addition of 1 nM homologous recombinant leptin to pre-pubertal male pituitary cells stimulated follicle-stimulating hormone secretion after 1 and 2 h of culture. Therefore, leptin signaling could also directly facilitate GTH secretion in male chub mackerel.