[Effect of the nitro analog of tetrapeptidamide and morphine on the cerebral blood supply].

A tetrapeptidamide nitroanalog and morphine produced an unmarked and short-lived increase in cerebral circulation, determined by the reduction of the vascular tone in both arterial brain systems. The tetrapeptidamide nitroanalog and morphine exerted a pronounced depressant effect on the nervous regulation of cerebral circulation by inhibiting the reflex constriction of the cerebral vessels. These effects of the drugs also occurred under blockade of GABA receptors. This indicates no relationship between the properties of the tetrapeptidamide nitroanalog and morphine and bicuculline-sensitive GABAergic processes.