Effects of temperature on S-potential producing cells and on neurons

Summary

Comparative studies were carried out regarding the effect of temperature on the plasma membrane potential recorded from “controller cells” (S-potential producing cells, isolated fish retina) and from “conductor cells” (spike conducting neurons, isolated frog dorsal root ganglion). The effect of temperature changes was pronounced and immediate on the controller cells but was small on the conductor cells, the results well agreeing with those presented in the preceding paper as to the effects of anoxia, CO₂ and NH₃. The resting potential of the horizontal cells was always hyperpolarized by heating from 20° (room temperature) to 30° C, and depolarized by cooling from 20° to 10° C, the light-induced responses being diminished at low and high temperatures. The temperature range between 18° and 23° C was optimal for the controller cell function, within this range the Q ₁₀ being 2–3 (4–5 mV/C°) for the horizontal cell resting potential. The hyperpolarized resting potential of the controller cell during anoxia was much less sensitive to temperature changes. The resting potential of the conductor cells in fresh preparations was slightly depolarized by heating and hyperpolarized by cooling, this membrane behavior being opposite to that of the controller cells. A strong temperature dependence, however, was observed in the spike duration of the conductor cells. The results suggest that there exist non-synaptic cellular interactions between adjacent amacrine cells in the retina, and between the conductor cell and its satellite cells in the dorsal root ganglion.