title: [Transformation of electrical activity in the myelinated nerve fibres of amphibia by 4-aminopyridine].
abstract: Using the extracellular recording we studied the effect of 4-aminopyridine (4-AP), a potassium channel blocker on the electrical activity of the myelinated nerve fibres of amphibia Rana ridibunda Pallas. Two main types of the reaction on 4-AP were established: extension of the action potential and multi-spike response. In some cases the nerve fibres with multi-spike response generated spontaneous activity without stimulation in the form of bursts of action potentials. During repetitive stimulation 4-AP decreased after-depolarization (at the beginning of the stimulation), the posttetanic after-depolarization and the development of posttetanic after-hyperpolarization. Using the paired stimulation it was established that the spike and after-depolarization of the second action potential depended on the size of after-depolarization after the first action potential. The effects of 4-AP were strongly time-dependent.
authors.forename: I V
authors.initials: IV
authors.lastname: Kuznetzova
authors.forename: D A
authors.initials: DA
authors.lastname: Evstigneev
authors.forename: N V
authors.initials: NV
authors.lastname: Glukhova
mesh_terms: D015761:4-Aminopyridine / Q000494:pharmacology*; D000200:Action Potentials / Q000187:drug effects*; D000818:Animals; D004558:Electric Stimulation; D066298:In Vitro Techniques; D009413:Nerve Fibers, Myelinated / Q000187:drug effects* / Q000502:physiology; D026902:Potassium Channel Blockers / Q000494:pharmacology*; D011895:Rana ridibunda
chemical_list: D026902:Potassium Channel Blockers; D015761:4-Aminopyridine