Neuropeptide Y modulates a G protein-coupled inwardly rectifying potassium current in the mouse hippocampus.
Neuropeptide Y (NPY) is an abundant brain peptide with endogenous antiepileptic activity. Here we examined the role played by Y1 receptors (Y1R) in the mouse hippocampus. Using whole-cell patch-clamp recordings, we show that hilar neurons in acute mouse hippocampal slices exhibit a G-protein coupled inwardly rectifying potassium (GIRK) current that is significantly enhanced during exogenous NPY application. NPY-mediated enhancement of GIRK current was observed on 47% of putative interneurons and was mimicked by application of Y1R specific agonist (Leu(31)Pro(34) NPY). Immunostaining revealed the presence of Y1R on cell somas of hilar NPY-containing interneurons. Thus, our results suggest that Y1R on hilar interneurons may act as a peptide autoreceptor.
Paredes
Mercedes F
MF
Department of Neurological Surgery,University of California, San Francisco, 513 Parnassus Avenue, San Francisco, CA 94143, USA.
Greenwood
Joel
J
Baraban
Scott C
SC
D000818:Animals; D019204:GTP-Binding Proteins / Q000378:metabolism*; D049452:Green Fluorescent Proteins; D006624:Hippocampus / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D008164:Luminescent Proteins / Q000096:biosynthesis / Q000235:genetics; D051379:Mice; D008822:Mice, Transgenic; D009478:Neuropeptide Y / Q000502:physiology*; D024661:Potassium Channels, Inwardly Rectifying / Q000819:agonists / Q000378:metabolism*; D011956:Receptors, Cell Surface / Q000819:agonists / Q000378:metabolism; D017476:Receptors, Neuropeptide Y / Q000819:agonists* / Q000378:metabolism
D008164:Luminescent Proteins; D009478:Neuropeptide Y; D024661:Potassium Channels, Inwardly Rectifying; D011956:Receptors, Cell Surface; D017476:Receptors, Neuropeptide Y; C097212:neuropeptide Y-Y1 receptor; D049452:Green Fluorescent Proteins; D019204:GTP-Binding Proteins