麻省理工学院：《电气工程与计算机科学》学习资料_Week11

Week 1l review What was covered Voltage gated ion channel Gating currents Model for Sodium and potassium channel State model Voltage gated channel Probabilistic gate. Probability that gate is open depends on voltage across membrane Gating currents The gate has charge on it.(Remember: charge on gate is why probably of being open changes with voltage. Therefore, the movement of the gate opening and closing causes a current. That is called the gating current What about sodium and potassium channels? Sodium and potassium channels can t just be modeled as one gate because Sodium channel has inactivation as well as activation Potassium channel has S-shape onset not exponential Use 4 gates to model single channel! Potassium

Week 11 Review What was covered: - Voltage gated ion channel - Gating currents - Model for Sodium and Potassium channel - State model Voltage gated channel in + out - Probabilistic gate. Probability that gate is open depends on voltage across membrane. Gating currents The gate has charge on it. (Remember: charge on gate is why probably of being open changes with voltage.) Therefore, the movement of the gate opening and closing causes a current. That is called the gating current. What about Sodium and Potassium channels? Sodium and Potassium channels can’t just be modeled as one gate because - Sodium channel has inactivation as well as activation - Potassium channel has S-shape onset not exponential Use 4 gates to model single channel! Sodium: Potassium: in in + + + - + + + + out out