GLUCAGON-LIKE PEPTIDE-1(7-36)AMIDE INDUCES THE RELEASE OF ASPARTIC-ACID AND GLUTAMINE BY THE VENTROMEDIAL HYPOTHALAMUS OF THE CONSCIOUS RAT

Glucagon-like peptide-1(7-36)amide (GLP-1(7-36)amide) and its own receptor have been found in the hypothalamus and brain stem of the rat. In an attempt to gain further insight into the role of this peptide in brain functioning we investigated the effects of GLP-1(7-36)amide on the release of excitatory amino acid neurotransmitters by the ventromedial hypothalamus using an experimental microdialysis approach. GLP-1(7-36)amide produced an immediate increase in the extracellular concentrations of aspartic acid and glutamine, p < 0.01 and p < 0.05, respectively. By contrast, extracellular concentrations of glutamic acid, alanine, threonine, and tyrosine were unaffected, The results of this study show a stimulatory effect of GLP-1(7-36)amide on the release of aspartic acid and glutamine by the ventromedial hypothalamus of the rat.