Figure 3.

Differential distribution of I_NaT and I_NaP in myenteric neurons. A, B, Top, Na⁺ current traces elicited by depolarizing voltage steps in myenteric neurons exhibiting either pure I_NaT (A) or mixed Na⁺ currents composed of I_NaP and I_NaT (B). Whole-cell recordings were made with intracellular biocytin (0.2%) added to the patch pipette solution for further morphological characterization. Bottom, Morphology of neurons revealed using streptavidin–Alexa Fluor 488. Note that the neuron expressing only I_NaT (A) has a Dogiel type I morphology with a single long axon, whereas the neuron with prominent I_NaP has a Dogiel type II morphology with multiple and ramified axons (B). C, D, Examples of morphologies of myenteric neurons with pure I_NaT (C) or mixed Na⁺ current (I_NaP and I_NaT; D). E, Percentage of cells with Dogiel type I and Dogiel type II morphologies expressing either I_NaT or I_NaP + I_NaT.