PHYL 2041 Lecture Notes - Lecture 4: Gap Junction, Inhibitory Postsynaptic Potential, Electrical Synapse

• School: Dalhousie University
• Department: Physiology
• Course: PHYL 2041
• Professor: Dr. Krueger

Document Summary

Lecture 4: synaptic transmission (chapter 6 in book) [synapse] = specialized points of cell contact between neurons where neurons can actually communicate. Classes of synapses: electrical synapses: (not as abundant as chemical synapses in brain) Gap junctions between neurons that permit the direct, passive flow of electrical current: structure: An electrical synapse is effectively a low-resistance pathway that exists between cells that allow current to directly flow from one cell to another and allows the exchange of small molecules between cells. Occur between cells and outside the nervous system, and the membrane potential changes between two connected neurons. Gap junctions are plaque-like structures in which the plasma membranes of the coupled cells are put side-by-side (intercellular space narrows to 3 nm) and is filled with electron-dense material. Cells that are connected via gap junctions can make ion channels, and once the cells line up, they form one continuous ion pore that connects the cytoplasm [gap junction channels].