To understand the molecular and physiological mechanisms underlying the regulation of reproduction by temperature, we examined changes in expression of genes encoding kisspeptin (kiss2), kisspeptin receptor (kiss2r) and three gonadotropin-releasing hormones (gnrh1, gnrh2 and gnrh3) in the brain and genes encoding gonadotropin (GTH) subunits (gpa, fshb and lhb) in the pituitary of grass puffer exposed to a low temperature (14°C), normal temperature (21°C) and high temperature (28°C) for 7days.