Abstract
The involvement of a central opiate mechanism in the operant escape behavior induced by dorsal central gray (DCG) stimulation was investigated in rats. Morphine (2-10 mg/kg, i.p.) produced a rise in the DCG-stimulation threshold, but did not suppress rapid running as an averse symptom. Naloxone alone affected neither the threshold nor the averse symptom. Nevertheless, naloxone counteracted morphine-induced increments in the threshold. These results suggest that the opiate system may be indirectly involved in certain aspects of the operant escape behavior induced by the DCG-stimulation.
