[Changes in the calcium action potentials of the neurons of the spinal ganglia in the rat in response to divalent cation substitution in the extracellular medium].
Rat dorsal root ganglion neurons were investigated by intracellular microelectrodes using current clamp technique. After elimination of sodium ions from the extracellular medium and addition of TEA pure "calcium" action potentials were recorded. Progressive and selective disturbance of such potentials was observed during continuous intracellular recording indicating a decrease in the calcium conductance while sodium and potassium conductances remained uneffected. Such a disturbance is supposed to be due to excessive influx of calcium, strontium or barium ions into the cell. The calcium component of the action potential was also dependent on the stimulation frequency, such dependence being different for strontium or barium solutions. Possible participation of current-dependent inactivation in the origin of this phenomenon is discussed.
N S
NS
Veselovskiĭ
E D
ED
Nalivaĭko
D000200:Action Potentials / Q000187:drug effects; D000818:Animals; D001464:Barium / Q000494:pharmacology*; D002118:Calcium / Q000502:physiology*; D005727:Ganglia, Spinal / Q000187:drug effects / Q000502:physiology*; D066298:In Vitro Techniques; D007473:Ion Channels / Q000187:drug effects*; D051381:Rats; D013324:Strontium / Q000494:pharmacology*
D007473:Ion Channels; D001464:Barium; D002118:Calcium; D013324:Strontium
Izmeneniia kal'tsievykh potentsialov deĭstviia neĭronov spinal'nykh gangliev krys pri zameshchenii dvukhvalentnykh kationov vo vnekletochnoĭ srede.