| Abstract: | Tyrosine hydroxylase activity correlated significantly with norepinephrine concentration and turnover, when results from regions containing predominantly noradrenergic terminals were compared, and with dopamine concentration and turnover when results from regions containing predominantly dopaminergic terminals were compared. Regions containing dopamine or norepinephrine cell bodies were characterized by higher tyrosine hydroxylase activities as compared to regions containing mostly nerve terminals. Higher levels of tyrosine hydroxylase activity and transmitter turnover were observed in regions containing dopaminergic terminals than in regions containing norepinephrine terminals. These findings are consistent with the view that tyrosine hydroxylase activity is linked to rates of catecholamine utilization by neurons in the CNS. |
