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Unformatted text preview: Ion Channels Ion Channels
Dr. McKemy 9/08/2008 Use concentration and electrical gradients. Are usually selective for specific ions.
◦ K+, Na+, Ca2+, Cl-. Most are “gated” by specific signals.
◦ Chemical or electrical. Ion channels. Ion Types of voltagegated ion channels Types of voltagegated ion channels Types of ligandgated ion channels Types of ligandgated ion channels Measuring ion channel activity Measuring ion channel activity Measuring single Na+ channels Measuring single Na Measuring single K+ channels Measuring single K Na+ versus K+ channels Na Functional states of voltagegated Na+ and K+ channels Functional states of voltagegated Na Not all K+ channels are created equal Not all K K+ channels K+ channels Toxins That Poison Ion Channels Toxins That Poison Ion Channels • TTX from Puffer fish
• Potent and specific for Na+ channels • Saitotoxin produced by dinoflagellates is a chemical homologue.
• “Red tide” and shellfish. Tetrodotoxinsensitivity of Na+ channel subtypes Tetrodotoxinsensitivity of Na ...
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This note was uploaded on 04/18/2010 for the course BISC 421 at USC.