Effect of modafinil and amphetamine on the rat catecholaminergic neuron activity.

We have studied the effect of modafinil and amphetamine, two waking drugs, on the electrical activity of central dopaminergic and noradrenergic neurons in the rat. Modafinil (128 mg/kg, i.p.) was unable to modify the firing pattern of these neurons, while amphetamine (2 or 5 mg/kg, i.p.) consistently inhibited their activity. A pretreatment with modafinil did not change thereafter the effect of amphetamine. Contrary to amphetamine, the waking effect of modafinil does not seem to be mediated by the catecholaminergic neuron activity per se.