Molecular neurobiology for practicing psychiatrists, Part 2: How neurotransmitters activate second messenger systems

Chemical neurotransmission begins when receptor occupancy by a neurotransmi tter is converted into an intracellular second messenger that carries the i nformation from the neurotransmitter deep into the target neuron. For clini cians, it is this transfer of neurotransmitter information all the way to t he genome that hypothetically explains the therapeutic actions of many psyc hotropic drugs, This also accounts for why drugs that modify neurotransmiss ion may take time to fully develop their clinical actions.