Yonsei Med J.  1999 Apr;40(2):112-117. 10.3349/ymj.1999.40.2.112.

4-Aminopyridine (4-AP) augments Ca(2+)-dependent action potential and changes oscillatory firing patterns in rat cerebellar Purkinje cells

• Seo WS
• Shin JH
• Suh CK

• KMID: 711623
• DOI: http://doi.org/10.3349/ymj.1999.40.2.112

Abstract

Intracellular recordings in cerebellar slice preparation showed that applications of 4-AP altered the pattern of oscillatory firing activity in Purkinje cells (PCs), especially yielding pronounced changes in action potential shape. 4-AP increased the amplitude and duration of action potential significantly and decreased the spike frequency. After 4-AP application, the duration of bursting was prolonged and the duration of after-burst hyperpolarization was progressively shortened. In all PCs tested, the rhythmicity of oscillatory firing activity was abolished completely at the steady state. These results suggest that 4-AP-sensitive currents determine the shape and frequency of individual Ca(2+)-dependent action potentials as well as maintaining oscillatory firing activity in PCs.

Keyword

Purkinje cells; oscillatory firing activity; 4-aminopyridine (4-AP); 4-AP-sensitive current

MeSH Terms

4-Aminopyridine/pharmacology*
Action Potentials/drug effects*
Animal
Calcium/physiology*
Electrophysiology
In Vitro
Oscillometry
Purkinje Cells/physiology*
Purkinje Cells/drug effects*
Rats
Rats, Sprague-Dawley