Gap Junction

2022-08-12: reference:

Gap Junction #

They are what forms electrical “synapses”. This isn’t just for say, long-distance communication or something - this is how multiple neurons respond and synchronize with one synaptic input and scale exponentially.

• Gap junctions are ~3-3.5nm. It is bridged by 1 gap junction channel and one Gap Junction in each cell. Usually you just see synapses depicted as a gap - no “connections” as much as there are just receptors. Dafuq?
• A connexon is a hexamer of (identical) connexins, each with 4 membrane-spanning regions. They rotate such that the connexon opens and closes like a camera shutter.

Coupling #

• A Role for Electrotonic Coupling Between Cortical Pyramidal Cells
  • Evidence for the existence of electrical coupling among cortical pyramidal cells, however, has been largely absent. A recent experimental study measured properties of electrical connections between pyramidal cells in the cortex deemed “electrotonic couplings.” These junctions were seen to occur pair-wise, sparsely, and often coexist with electrically-coupled interneurons.
  • Apparently electrical coupling among interneurons occurs through the gap junctions.
• [High-frequency population oscillations are predicted to occur in hippocampal pyramidal neuronal networks interconnected by axoaxonal gap junction]