Intracellular signals mediating the food intake-suppressive effects of hindbrain glucagon-like peptide-1 receptor activation.

ABSTRACT: Glucagon-like peptide-1 receptor (GLP-1R) activation within the nucleus tractus solitarius (NTS) suppresses food intake and body weight (BW), but the intracellular signals mediating these effects are unknown. Here, hindbrain (fourth i.c.v.) GLP-1R activation by Exendin-4 (Ex-4) increased PKA and MAPK activity and decreased phosphorylation of AMPK in NTS. PKA and MAPK signaling contribute to food intake and BW suppression by Ex-4, as inhibitors RpcAMP and U0126 (fourth i.c.v.), respectively, attenuated Ex-4's effects. Hindbrain GLP-1R activation inhibited feeding by reducing meal number, not meal size. This effect was attenuated with stimulation of AMPK activity by AICAR (fourth i.c.v.). The PKA, MAPK, and AMPK signaling responses by Ex-4 were present in immortalized GLP-1R-expressing neuro

SUBMITTER: Hayes MR 

PROVIDER: S-EPMC3108145 | biostudies-literature | 2011 Mar

REPOSITORIES: biostudies-literature