Agonist- and Reflex-Evoked Internalization of Metabotropic Glutamate Receptor 5 in Enteric Neurons

摘要: We demonstrate that metabotropic glutamate receptor 5 (mGluR5) is present in the guinea pig ileum. A punctate ring-like distribution of immunoreactivity found on soma a subset neurons, consistent with an association mGluR5 plasma membrane. mGluR5-containing cells submucosal plexus are predominantly noncholinergic and contain vasoactive intestinal peptide, marker secretomotor neurons. Using immunocytochemistry conjunction confocal microscopy, we show undergoes agonist- reflex-evoked internalization inhibited by group I antagonist 1-aminoindan-1,5-dicarboxylic acid. In addition, mGluR antagonists reduce distension-induced phosphorylation cAMP-responsive element-binding protein enteric neurons attenuate both glutamate- agonist-induced depolarizing responses slow synaptic events These findings support idea mGluRs play role reflexes suggest might be major mechanism for regulation activity.