Figure 3.

Temperature up to 40°C does not lead to acute neuronal damage. A, Tridimensional plot showing that temperature-induced firing is reversible during cooling of the bath solution. Firing frequency was extracellularly recorded from a pyramidal neuron and plotted against temperature and recording time. Note the reversibility of the temperature-induced firing. B, Whole-cell recordings of the voltage responses of a pyramidal neuron to hyperpolarizing and depolarizing current injections before (−100 and +60 pA) and during (−120 and +60 pA) a brief exposure to hyperthermic temperature; the cell showed very similar firing patterns before and during hyperthermia. C, Pyramidal neurons exhibit normal electrophysiological responses to current injections (−340 and +160 pA) after >20 min in hyperthermic conditions. The resting membrane potential of this cell after 20 min at 39°C was −59 mV. Intracellular recordings shown here were performed using K-gluconate internal solution.