PHGY 311 Lecture Notes - Lecture 5: Apamin, Astrocyte, Repolarization

• School: McGill University
• Department: Physiology
• Course: PHGY 311
• Professor: Reza Sharif

Document Summary

Shift toward hyopertonic envvp release to bring back to set point. 3 regulatory mechanisms that increase firing rate from lect 1:taurine release from astrocytes etc If vp neurons were to increases there firing rate and fire continuously: this leads to a fatigue of the release process. You get a decrease in the amount of vp released very quickly even though the firing is maintained . Cells transition from irr firing to phasic firing to avoid secretory fatigue. As osmolarity around the cell increases, transition from irr to phasic, the mean firing rae increases and the frequency within the burst increases and the duration of the burst also increases. Was not know if the same neuron was doing all these pattern transitions, found out yes . Accumulation of k outside the neuronbc of the outward movement of k during the repolarizing phase of the. Ap, and if u increase the frequ, the more the k outside.