Effect of amphetamine on the pressor response to tyramine: Formation of p‐hydroxynorephedrine from amphetamine in man

Abstract

The effect of amphetamine on the pressor sensitivity to the indirectly acting amine, tyramine, and to norepinephrine was determined in 6 male patients. Acute intravenous administration of amphetamine increased the sensitivity to both tyramine and norepinephrine to 200 to 300 per cent of control. In contrast, long‐term administration reduced the sensitivity to tyramine to 60 to 70 per cent of control, while the sensitivity to norepinephrine was still enhanced. A likely explanation for the diminished response to the indirectly acting amine is depletion of norepinephrine. In this study it was demonstrated that human sub;ects metabolize 8H‐amphetamine to p‐hydroxynorephedrine, an amine known to displace norepinephrine from the neuron terminal.