Bufo marinus oocytes as a model for ion channel protein expression and functional characterization for electrophysiological studies.

Oocytes from Xenopus laevis are commonly used as an expression system for ion channel proteins. The aim of this study was to determine whether oocytes from the Colombian native toad, Bufo marinus, could be used as an alternative expression system for ion channel protein expression and functional characterization using the two-microelectrode voltage clamp method. B. marinus oocytes and X. laevis were isolated and cultured in similar conditions. The mean resting membrane potential of B. marinus oocytes was similar to that of X. laevis oocytes as well as the whole-cell basal currents. The potassium ion channel Kv1.1 was successfully expressed in B. marinus oocytes and showed a typical outward rectifying current. Potassium channel blockers reduced these currents. The similarities on electrical properties and expression of ion channel proteins show that B. marinus oocytes can be used effectively to express these proteins, making these cells a viable heterologous system for the expression of ion channel proteins and their electrophysiological characterization. Copyright 2004 S. Karger AG, Basel