Figure 4.

Ca²⁺ channel currents in afferent neurons innervating the proximal urethra (A) and distal urethra (B) with TTX-sensitive action potentials. HVA Ca²⁺ channel currents were induced by depolarizing pulses to 0 mV from the holding potential of −40 mV (left panels). LVA, T-type Ca²⁺ channel currents were induced by depolarizing pulses to −40 mV from the hyperpolarized holding potential of −90 mV (right panels). Note that the fast-inactivating T-type Ca²⁺ channel current was found in the distal urethral neuron but not in the proximal urethral neuron.