Dextroamphetamine infusions in normals result in correlated increases of plasma β-endorphin and cortisol immunoreactivity

Stress induces behavioral and hormonal alterations. In experimental and clinical studies, amphetamine administration may simulate or potentiate such effects. The endogenous opioid system has been implicated in the modulation of stress effects. Dextroamphetamine, 0.3 mg./kg. and placebo were infused on separate days in a double-blind cross over design to eight normal volunteers. At 30 minutes post infusion, plasma β-endorphin immunoreactivity was significantly (p <0.05) increased. The increase ws significantly correlated (r = 0.76, p = 0.05) with volunteers' cortisol responses.