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S NAKAJIMA

Publications and source records attributed to S NAKAJIMA.

At least 19 recordsLinked to original sources
PubMed1964

ADAPTATION IN STRETCH RECEPTOR NEURONS OF CRAYFISH.

Two factors involved in the adaptation in stretch receptor cells of crayfish were separated and studied: (i) the decline of the rate of discharge during intracellular application of constant current and (ii) the decline of generator potential during sustained stretch. The change in generator potential with time was essentially identical in both rapidly and slowly adapting cells. The slowly adapting cells continued to discharge throughout the application of depolarizing currents, whereas the rapidly adapting cells stopped discharging while the current was applied. The different rates of adaptation are therefore attributable to the difference in the properties of the electrically excitable membranes rather than the properties which produce generator potentials.

Acclimatization↗
PubMed1964

EEL ELECTROPLAQUES: SPIKE ELECTROGENESIS WITHOUT POTASSIUM ACTIVATION.

Measurements with the voltage clamp technique demonstrate that only an early conductance increase occurs during spike electrogenesis of eel electroplaques. The delayed increase which is characteristic of spike electrogenesis in many other cells is absent. Instead, the membrane resistance increases two- to threefold above its resting value. The brief initial increase in conductance is due to sodium activation followed by rapid sodium inactivation. The influx of sodium causes an inward current of up to 80 ma/cm2. The inward current is abolished by eliminating the sodium from the normal medium (substitution of choline chloride for NaCl); by blocking sodium activation with tetrodotoxin; or by causing sodium inactivation through enrichment of the potassium in the medium. The delayed increase in membrane resistance is not affected by eliminating sodium influx, nor by substituting various impermeable anions for the chlorine of the normal medium. Thus, the increase in resistance signifies the occurrence of potassium inactivation which is unmasked by the absence of potassium activation.

Animals↗