title: Transient receptor potential canonical channels regulate the induction of cerebellar long-term depression.
abstract: In the cerebellum, synaptic strength at the synapses between parallel fibers and Purkinje cells is best known to be modulated via metabotropic glutamate receptor 1 (mGluR1)-dependent cerebellar long-term depression (LTD). An increase in intracellular calcium levels plays an important role in inducing mGluR1-dependent cerebellar LTD. Downstream of mGluR1, there are two major sources of calcium: transient receptor potential canonical (TRPC) channels and inositol trisphosphate receptors (IP(3)R). IP(3)R triggers a calcium release from the intracellular calcium store. Here, we show that TRPC channels mediate mGluR1-evoked slow currents to regulate cerebellar LTD in Sprague Dawley rats. We found that the inhibition of TRPC channels blocks the induction of cerebellar LTD. Moreover, we show that processes known to underlie cerebellar LTD induction, such as increases in intracellular calcium concentration, the activation of protein kinase C, and the internalization of GluR2, are also hindered by blocking TRPC. These results suggest that the mGluR1-evoked activation of TRPC channels is required for the induction of cerebellar LTD.
authors.affiliation: Department of Physiology, Biomedical Science, College of Medicine, Seoul National University, Chongro-gu, Seoul 110-799, Korea.
authors.forename: Hong Goo
authors.initials: HG
authors.lastname: Chae
authors.forename: Sung Ji
authors.initials: SJ
authors.lastname: Ahn
authors.forename: Yun Hwa
authors.initials: YH
authors.lastname: Hong
authors.forename: Won Seok
authors.initials: WS
authors.lastname: Chang
authors.forename: Jun
authors.initials: J
authors.lastname: Kim
authors.forename: Sang Jeong
authors.initials: SJ
authors.lastname: Kim
mesh_terms: D000818:Animals; D002531:Cerebellum / Q000502:physiology*; D005260:Female; D036881:Long-Term Synaptic Depression / Q000502:physiology*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D018094:Receptors, Metabotropic Glutamate / Q000378:metabolism*; D050051:Transient Receptor Potential Channels / Q000378:metabolism*
chemical_list: D018094:Receptors, Metabotropic Glutamate; D050051:Transient Receptor Potential Channels; C108822:metabotropic glutamate receptor 2