[The effect of cobalt on the dynamics of membrane-bound calcium in the cerebral cortex structures]

Cobalt (Co2+) influence on calcium bound (Cab2+) dynamics detected by a fluorescent chlorotetracyclin probe (CTC), as well as bioelectric activity were studied in the feline vital brain cortex preparation with contact microscopy and microelectrode technique. It has been found that Co2+ applied on the preparation surface or injected ionophoretically into microzones under microscopy produced a distinct decrease of CTC-Cab2+ fluorescence intensity. This indicates a decrease of Cab2+ content in the hydrophobic membrane loci. The effect is reversible and depends on Co2+ concentration. Neuronal excitation appeared after the fluorescence decrease up to 5-12% to the start level. It has been concluded that Cab2+ content dynamics plays an important role in the Co2+ "seizure" discharges mechanisms in the cortex.