Interaction between Kisspetin and Dopamine in the Regulation of in vitro LH Release in Prussian carp (Carassius gibelio Bloch, 1782) Females at the Time of Gonad Recrudescence and Spawning Period

The aim of the present study was to demonstrate the in vitro response (LH release) of Prussian carp pituitary cells to mammalian kisspeptin in static incubations. Pituitary glands were collected at two periods of the season (at the time of gonad recrudescence or spawning period) from untreated fish or those with dopaminergic system blocked in vivo by injection of pimozide - a dopamine receptor antagonist. LH measurement (by ELISA method) have shown that there was no significant impact of kisspeptin on the level of this gonadotropin at both investigated seasons of the year if pituitary glands for the study were collected from untreated females. In case of fish pre-treated with pimozide there was a significant stimulation of LH release in both investigated seasons. The results demonstrate the direct effect of kisspeptin on LH release from the Prussian carp gonadotropic cells, dependent on the strength of dopamine inhibition on LH secretion.