Zentaro Ito

Electrical activities of neurons in the sliced human cortex in vitro

Abstract Slices from the human cerebral cortex which were sacrificed at therapeutic or diagnostic operations could be kept alived in an artificial medium for more than 9 h. Activities of 18 single neurons were recorded from six slices. These neurons were classified into four types according to their latencies and response patterns to electrical stimulation of the white matter: (1) antidromically activated neuron, type A; (2) orthodromically activated neuron with a short latency, type B; (3) orthodromically activated neuron with a long latency, type C; and (4) orthodromically activated neuron with repetitive discharges, type D. Out of 18 neurons, 6 neurons belonged to type A, 4 to type B, 6 to type C and 2 to type D. Type A, B and C neurons were recorded in both the inner and the outer layers of the grey matter, and two type D neurons were recorded in the inner layer. Eight neurons showed spontaneous discharges, with interspike intervals of from 45.5 to 320.4 msec, for more than 30 min. Two type D neurons showed no spontaneous discharge at all. Spontaneous discharge of type A neuron was inhibited by a subthreshold stimulus given to the white matter for about 430 msec. Discussion was devoted to the function of these types of neurons and the existence of the autofiring neurons in the cortex was suggested.

The Emergency STA-MCA Bypass Evaluated by the Induced-Functional EEG Analysis in Acute Ischemic Stroke

The extra-intracranial arterial bypass (EIAB) has been performed widely for ischemic stroke patients with transient ischemic attacks (TIA), reversible ischemic neurologic deficits (RIND), and complete strokes.