Available Online: http://www.ejpau.media.pl/volume2/issue2/fisheries/abs-02.html
EFFECTS OF INTRAVENTRICULAR MELATONIN MICROINJECTIONS ON HYPOTHALAMIC CATECHOLAMINE ACTIVITY IN CARP FEMALES DURING A YEAR
Włodzimierz Popek, Piotr Epler
Assays, made on 64 mature carp females aged 5 years, were performed during the spawning season (summer) and in mid-winter. Some fish were subject to intraventricular melatonin microinjections, while other had their pineal gland excised. Intensity of fluorescence in the hypothalamic aminergic nuclei was determined with the fluorescence histochemical method. The lowest fluorescence intensity was revealed in those individuals lacking the pineal gland, the highest intensity being typical of the fish subject to intraventricular melatonin microinjections. In the winter series, all the fish showed a similar fluorescence intensity in the hypothalamic region studied. The results demonstrate a relationship between the pineal gland, melatonin, and the hypothalamic aminergic system, present in carp during the spawning period.
Key words: pineal gland, melatonin, hypothalamic catecholamines, hormonal control of maturity, carp..