NEUR3101 Lecture Notes - Lecture 13: Ion, Reversal Potential, Pacemaker Current
Document Summary
Voltage-activated na+ channels in dendrites - na inward current. Amplitude is conserved across dendritic membrane after about half a mm (half way approx) (whole dendrite is approx 1mm) Sustained potassium channels - like delayed rectifier currents. Increases as you get away from sona into the dendrites. Doesn"t makes sense to invest energy and resources to push proteins out unless it is needed from an evolutionary perspective. Activation curve looks like a regular deactivation cure (backwards) - fits into a boltzmann curve. Some are open at normal resting potential - therefore, they will be open when the cell is at rest. Paly in an important role in setting membrane potential in those neurons. Found in retina - not change in voltage but change in nucleotide. Slow on and off kinetics (~50 ms to seconds) Once open, they stay open for a while. Hcn channels influence the input resistance and effective membrane time constant. Opening of cell causes hyperpolarisation: drives against depolarisation.
