electrical synapse

what do electrical synapses allow?

direct transfer of ionic currents

where do electrical synapses occur?

at specialized sites called gap regions

what do gap regions do?

interconnect many non-neural cells, function as electrical synapses

how much are gap regions separated by?

3 nm

what spans electrical synapses?

connexins

how many subtypes of connexins are there?

20

how many connexins submits form the connexon channel?

6

how many connexins form the gap junction channel?

2

how big is the pore of a gap junction?

1-2 nm

what direction do electrical synapses occur?

both, they are bidirectional

cell connected by gap junctions are _____

electrically coupled

what does an Ap in the presynaptic neuron cause?

a small ionic current to flow across the gap junctions

what does the small ionic current cause in the second neuron?

a post synaptic potential

because electrical synapses are bidirectional…

the second neuron will induce a post synaptic potential in the first neuron

measurement of PSP

usually small, 1 mV or less

_______ PSPs may strongly excite a neuron

several

electrical synapses are (slow/fast)

fast

where are electrical synapses found in invertebrate species?

between sensory and motor neurons

inferior olive

can generate both oscillations of membrane voltage and action potentials

gap junctions allow neighboring cells to…

share chemical and electrical signals