EN
This study was undertaken to ascertain functional changes in areas of ipsi- and contralateral motor cortex involved with the ischemic incidences following experimental closing of fl ow in cervical aorta uni- (right) or bilaterally when recordings of motor evoked potentials induced with magnetic fi eld (MEPs) were performed.Aims of this study were (1) ascertaining changes in parameters of recordings in motor evoked potentials (MEPs) following experimental ischemic conditions, (2) histological verifi cation of range in pathological changes within motor cortex neurons following ischemia, (3) estimation the correlation between duration of ischemia and changes in activity of cortico-spinal neurons. Studies were performed on 24 Wistar rats. Recordings of MEPs induced in the left motor cortex were performed from right sciatic nerve.Signifi cant fl uctuations in MEPs amplitudes from 4.5 mV to 1.5 mV were commonly found within 8 minutes from the experiment onset what might indicate on changes in excitability and transmission of certain number corticospinal neurons. Contrary to the previously found changes in MEPs latencies we observed more often the reversible changes of amplitude parameter. The time of 6 minutes after the signifi cant ischemic incidence is not critical for irreversible and persistent changes in activity of cortico-spinal neurons.