Receptors for the incretin glucagon-like peptide-1 are expressed on neurons in the central nervous system

Glucagon-like-peptide-1 is an incretin hormone that also has neuroprotective properties. Here we analyse where glucagon-like-peptide-1 receptors are expressed in the brain. The receptor is found only on neurons, not on glia cells. The pyramidal cell layer of the CA region and the granule cell layer of the dentate gyrus in the hippocampus show intense staining. In the neocortex, larger pyramidal neurons express the receptor. In the cerebellum, only Purkinje neurons express the receptor. Dendrites of larger neurons were stained; in particular, pyramidal cells in area CA and dendrites of Purkinje cells. The fact that the receptor is located on neurons and dendrites suggests that the neuroprotective action is caused by the modulation of neuronal excitation