The accumulation of p-hydroxyamphetamine by brain homogenates and its role in the release of catecholamines

p-Hydroxyamphetamine (p-OHA) is accumulated by synaptosome enriched preparations from both striatal and cortical tissues. In studies with P₂ preparations from rat cortex the accumulation of $\text{p-}\text{OHA}\text{-}{}^3\text{H}\text{]}$ was shown to be temperature dependent but different from the process involved in the accumulation of norepinephrine-³H](NE³H]) by this tissue. The uptake of p-OHA was less sensitive to DMI and cocaine and had a different time dependency. The accumulation of p-OHA was concentration dependent and did not show evidence for saturation at concentrations up to 10 μM, The relationship between p-OHA uptake and catecholamine release from the striatum and cortex was also examined. The results suggest that much of the observed cortical uptake of p-OHA is not due to the neuronal carrier for norepinephrine.