Summary
Penicillin-induced paroxysmal depolarization shifts (PDS) are followed by prolonged afterhyperpolarizations of about 2 seconds duration. Intracellular injection of EGTA blocked a late component of the afterhyperpolarizations; an early one lasting up to one second was only slightly reduced by EGTA. It is concluded that afterhyperpolarizations following penicillininduced PDS comprise different components: an initial one lasting up to one second which is not Ca2+-dependent and a slow one lasting up to two seconds which is caused by a Ca2+-dependent K+ current.
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Domann, R., Dorn, T. & Witte, O.W. Calcium-dependent potassium current following penicillin-induced epileptiform discharges in the hippocampal slice. Exp Brain Res 78, 646–648 (1989). https://doi.org/10.1007/BF00230253
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DOI: https://doi.org/10.1007/BF00230253