I'm trying to learn more about polarized epithelial cells of the gut. I am familiar with classic brush border transporters localized to the apical memebrane to facilitate nutrient absorption. I am wondering though, where are ion channels located? I would guess basolaterally since they would be exposed to the extracellular space. I would appreciate a primary reference showing the location of voltage-gated channels in particular as I could not find them myself.
Well, that's a first for me. I wouldn't have guessed gut cells would have voltage-gated channels. This article describes voltage-gated sodium channels on both the luminal and basolateral membranes:
Barshack, I., Levite, M., Lang, A., Fudim, E., Picard, O., Ben Horin, S., & Chowers, Y. (2008). Functional voltage-gated sodium channels are expressed in human intestinal epithelial cells. Digestion, 77(2), 108-117. http://www.ncbi.nlm.nih.gov/pubmed/18391489