galanin or morphine significantly decreased thyroid hormones concentration after injections compared to before injection

Previous studies have shown that galanin is an orexigenic peptide that inhibits the activity of Hypothalamus –Pituitary – Thyroid (HPT) axis. It is also proved that galanin increases food intake via neuropeptide Y pathway. Morphine is an alkaloid opiates that effect on thyroid hormones concentration via Agouti Related Protein and increases dopaminergic neurons activity in median eminence. The aim of this study was to determine the influence of the interaction between galanin and morphine on thyroid hormones concentration.Twenty-one male Wistar rats ( 200-250 g) were randomly divided 3 groups. The groups received 200ng galanin, 1µg morphine and 200ng galanin together with 1µg morphine in third cerebral ventricle in volumes of 3 μl. Blood samples were collected one day before injection and untill 24 hours after that. The plasma was analyzed by Radioimmunoassay technique to determine T3 and T4 concentrations. Brain slices were taken to ensure that the place of the canulae was right. The results indicated that galanin or morphine significantly decreased thyroid hormones concentration after injections compared to before injection (p