[Reversal potential of the EPSP of frog motoneurons].
The current-chop technique has shown that I-V characteristic of the membrane are nonlinear in lumbar motoneurons of isolated perfused frog spinal cord. Input resistance of the membrane decreased with depolarization when constant current was applied during 0.1-1.0 s. However, injection of current 40-60 nA during 1-2 min led to an increase of the membrane resistance to the initial value. As a result the membrane potential could be shifted to the positive level up to +50 mV and more. Monosynaptic excitatory postsynaptic potentials evoked by stimulation of the brainstem or by microstimulation of ventrolateral tract fibres were found to reverse completely at a positive level of the membrane potential. In most cases the reversal potentials ranged between 0 mV and -10 mV.
D000818:Animals; D004525:Efferent Pathways / Q000502:physiology; D004553:Electric Conductivity; D005071:Evoked Potentials; D066298:In Vitro Techniques; D008526:Medulla Oblongata / Q000502:physiology*; D009046:Motor Neurons / Q000502:physiology*; D011895:Rana ridibunda; D012154:Reticular Formation / Q000502:physiology*; D013126:Spinal Nerve Roots / Q000502:physiology; D013569:Synapses / Q000502:physiology; D009435:Synaptic Transmission
Potentsial ravnovesiia monosinapticheskikh VPSP v motoneĭronakh liagushki.