Biogenic Amine Concentration in Testes of Rats at Different Ages

The concentrations of norepinephrine, dopamine, histamine and serotonin were investigated in the testes of Wistar rats at 1, 5, 10, 20 and 120 days of age. All these amines were present at their maximal level at day 1 of age, and showed a considerable decrease through the different age periods studied, with minimal levels at adulthood of about 1% that of the neonatal period. These results were paralleled by the positive histofluorescent reactions for dopamine and serotonin which appeared to be located in the wall of seminiferous tubules and interstitial cells, respectively. (Endocrinology88: 351, 1971)