[Intensification of neurogenic spasms of the cerebral vessels by naloxone].

Naloxone was shown to induce a slight increase of the blood supply to the brain, an elevation of blood pressure and an enhancement of the bioelectrical activity in the sympathetic nerves. Unlike opioid peptides, naloxone was found to exert a marked alleviating effect on the nervous control of the cerebral circulation. The drug increases neurogenic spasms of the cerebral vessels that is followed by an enhancement of vasomotor and somatosympathetic reflexes. The data obtained indicate the role of the opioid system in the central regulation of the cerebral circulation.