Effect of 6-hydroxydopamine on electrical self stimulation of the brain

In rats, after a single intracisternal injection of 6-hydroxydopamine (6-OHDA) electrical self stimulation was reduced by approximately 50%. The concentrations of noradrenaline and dopamine in the brain were reduced by 83%. A second injection of 6-OHDA reduced the concentration of these amines to 7% of control values and virtually eliminated self stimulation.