Sep 26, 2013
Postsynaptic Receptors
There are Ionotropic and Metabotropic Receptors
Ionotropic receptors open ion channels directly and the effects are quick. Only the first neurotransmitter is involved.
Metabotropic receptors are opened indirectly by a second neurotransmitter. The effects of metabotropic receptors are usually pretty slow, meaning they last longer.
In a metabotropic effect, a neurotransmitter binds to the receptor and activates a protein that is attached to the inside of a cell membrane (the G Protein) which initiates a chemical change within the cell to finally produce the second messenger. Only then do the ion channels open in the postsynaptic membrane.
