Central Nervous System Neurotransmitters, Receptors, and Drug Targets

pediagenosis    June 09, 2021    Medicine , Pharmacology    Comment   

Central Nervous System Neurotransmitters, Receptors, and Drug Targets

Many substances within the CNS modulate neurotransmitter actions. ACh and norepinephrine (NE), predominant in the PNS, also function in the CNS. Dopamine and 5­HT (serotonin)—more prominent in the CNS—and peptides such as endorphins are important in CNS function. Transduction mechanisms for neurotransmitter action are similar to those in the PNS: ionotropic types include voltage­gated ion channels (respond to membrane potential changes) and ligand­gated ion channels (alter membrane ion permeability in response to ligands such as neurotransmitters or drugs). Metabotropic types include GPCRs and involve second­messenger pathways (affect ion channels or bio­chemical reactions). Drugs affect various sites along neuronal pathways, including neurotransmitter synthesis, storage, and release; receptor activation and inhibition; modulation of intra­synaptic neurotransmitter metabolism or reuptake; and direct second­messenger pathway effects.