Fig. 1.

Hypoxia causes an increase inG_N, an inward shift inI_BH, and a decrease in the amplitude of inward relations in TC neurons. A₁, Voltage-clamp traces obtained with an electrode containing KMeSO₄ show the inward and outward currents evoked by depolarizing and hyperpolarizing voltage steps before (CONTROL), during (HYPOXIA), and 5 min after hypoxia (RECOVERY). Note the marked increase in instantaneous current and the small increase in steady-state current evoked by the hyperpolarizing voltage steps during hypoxia. A₂, Continuous trace shows the inward current activated during hypoxia. B₁,I–V plot obtained from the same neuron as in A₁ shows the substantial increase inG_N during hypoxia. In this and otherI–V plots in the following figures,open circles, open squares, andclosed triangles represent data obtained before, during, and after hypoxia, respectively. B₂, Plot of the difference current I_dif (i.e., the instantaneous current measured during hypoxia minus the instantaneous current measured in control conditions) from the data shown in B₁. In this and the following figures,V_h indicates the holding potential (for further details, see Materials and Methods).