Most of known and well studied ion channels are surface (plasma membrane) channels. Their study has been possible because of the spectacular development of the patch clamp technique. With this method, a glass pipette can be approached from the exterior and landed on the plasma membrane to record ion channel currents under conditions of voltage control. Intracellular membranes are normally unavailable for the patch clamp technique. The alternative strategy is to extract the intracellualr membranes we are interested in (subcellular fractionantion and differential centrifugation) and then incorporate vesicles containing the channel into an artificial planar lipid bilayer. The technique is one of the first methods developed to study ion channels and is still the best method to study single ion channels from intracellular membranes. Planar lipid bilayers allow full manipulation of ionic and pharmacological conditions around the ion channel. Thus, we study how the open probability of RyR2 incorporated in a planar lipid bilayer is affected when changing the Ca2+ concentration in the face that noramally is exposed to the interior of the SR.
Subscribe to:
Post Comments (Atom)
No comments:
Post a Comment