Summary.
This study examines the age-associated changes in noradrenaline (NA), dopamine (DA), 3,4-dihydroxyphenyl-acetic acid (DOPAC), serotonin (5-HT) and 5-hydroxy-3-indoleacetic acid (5-HIAA) in different brain areas of rats. DA and DOPAC concentrations in striatum increased at third month of age, remaining without significant variations until 12th month of age, and decreasing in 24-month-old rats. DA concentration dropped in hippocampus, amygdala and brainstem of 24-month-old-rats, whereas DOPAC levels decreased only in hippocampus. These changes suggest an age-dependent deficit of the dopaminergic system, presumably related to a reduced number/activity of DA nigrostriatal and mesolimbic neurons. An age-induced decline in NA content was found in the pons-medulla, the area containing NA neuronal bodies. Concentrations of 5-HT were reduced with aging in frontal cortex, showing a tendency to decrease in all brain areas examined. The increased 5-HIAA/5-HT ratio found in frontal cortex, amygdala and striatum suggests an age-related decreased synthesis and an accelerated 5-HT metabolism. The 5-HIAA content decreased in brainstem of the oldest rats. These findings point to a selective impairment of nigrostriatal and mesolimbic DA in aging rats, whereas reductions in NA were restricted to cell bodies region and 5-HT showed changes of different extent in areas of terminals and neuronal cell bodies.
Similar content being viewed by others
Author information
Authors and Affiliations
Additional information
Received March 16, 1999; accepted June 16, 1999
Rights and permissions
About this article
Cite this article
Míguez, J., Aldegunde, M., Paz-Valiñas, L. et al. Selective changes in the contents of noradrenaline, dopamine and serotonin in rat brain areas during aging. J Neural Transm 106, 1089–1098 (1999). https://doi.org/10.1007/s007020050225
Issue Date:
DOI: https://doi.org/10.1007/s007020050225