[Influence of phenamin on the reaction of cortical neurons evoked by stimulation of mesodiencephalic structures].

Experiments set upon 32 cats demonstrated that d, l-amphetamine (1-3 mg/kg, intravenously) augmented the number of responding units, modified the structure of the response and the intensity of the reaction from the sensorimotor (somatosensory) cortex neurones following stimulation of the mesencephalic reticular formation. Weakening of phasical and significant intensification of tonic reactions from the lateral hypothalamus was noted, this being attended by a rise of areactive neurones. A single stimulation of the antero-medial hypothalamus evoked inhibitory responses more often than it did in controls. Its rhythmical stimulation was less frequently accompanied by activation which stressed the inhibitory nature of the cortical response. It is suggested that the action of d, l-amphetamine on the cortex depends not only upon mobilization of brain stem reticular formation, but also on the greater reticulo-hypothalamic interaction, as well as on the direct excitation (stimulation) of the hypothalamic centres.