BIO304H5 Lecture Notes - Lecture 6: Squid Giant Axon, Voltage Clamp, John Zachary Young
Document Summary
2- voltage clamp technique and the squid giant axon. Squid giant axon prep by jz young. Can hold and altar vm during electrophysiological experiments. Action potential required understand how gna and gk change during the course of action potential. At rest gna and gk are made up of leak channels. When vm is depolarized (due to an excitatory graded potential) voltage-gated na+ and k+ channels open to contribute to gna and gk. Vm keeps changing during ap and the conductance of voltage-gated. The first triangle (a) is a voltage amplified that read vm. One electrode inside the axon and one electrode outside the axon. Amplifier is comparing the command voltage to the voltage inside the axon. The amplifier injects positive depolarizing current into the axon, raising the vm. Has a resistor (r) between its two inputs. This is the one the experimenter looks at. As you know the resistance, the voltage. Use vc to hold voltage at -65mv.
