[The effect of pikamilon and fenibut on the blood supply of the brain at rest and under gravitational exposures].

The effects of Picamilonum, 10 mg/kg, and Phenibutum, 50 mg/kg, on the cerebral blood flow, oxygen saturation and vascular reactivity in the cerebral cortex, thalamus, and hypothalamus were studied at rest during antiorthostatic hypokinesia and while rocking in antiorthostasis. Picamilonum was shown to have more steady vasodilatory effect, but it decreased a cerebrovascular response to CO2 and O2 inhalation. The reactivity of cerebral vessels to antiorthostasis under the influence of the drugs inversed, that of cerebrovascular vessels to CO2 inhalation decreased. Picamilonum enhanced vasoconstrictory responses to CO2 inhalation, whereas Phenibutum decreased it. With the combined effects of Phenibutum and Picamilonum, while rocking in antiorthostasis, a phase of vasodilatation was not observed and oxygen saturation and cerebrovascular reactivity were decreased.