Inhibition of Biogenic Amine Uptake by Hydrogen Peroxide: A Mechanism for Toxic Effects of 6-Hydroxydopamine

Hydrogen peroxide, dialuric acid, or 6-hydroxydopamine inhibited the uptake of dopamine, norepinephrine, and serotonin into rat brain synaptosomal preparations. The addition of catalase protected all systems, but catalase was only partially protective for 6-hydroxydopamine acting upon catecholamine uptake. The data show that 6-hydroxydopamine generates hydrogen peroxide and that hydrogen peroxide can damage the biogenic amine uptake systems. Part of the damage caused by the 6-hydroxydopamine that accumulates in the catecholamine nerve terminals in vivo may be attributed to the hydrogen peroxide.