The Sarcoplasmic Reticulum Potassium Channel
The conduction, gating, and pharmacological properties of the sarcoplasmic reticulum (SR) K+ channel have been well characterized (Coronado et al., 1980; Coronado and Miller, 1980; Labarca et al., 1980; Miller, 1982). It is a relatively “simple” channel in that it exists in only two states, open or closed, with quite slow (seconds) transitions between the two, is gated by voltage only, and does not inactivate. It thus provides an excellent vehicle for studying possible lipid effects on a channel protein. In turn, the artificial bilayer system is the ideal means for studying lipid effects because both the membrane composition and the ionic milieu can be determined and manipulated by the experimenter. The topic of this chapter is the role of the electrical charge of the bilayer in the observed conduction characteristics of the SR K+ channel in artificial bilayers.
KeywordsCharge Density Sarcoplasmic Reticulum Surface Potential Lipid Monolayer Channel Mouth
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