title: Ryanodine Receptors Selectively Interact with L Type Calcium Channels in Mouse Taste Cells.
abstract: WE REPORTED THAT RYANODINE RECEPTORS ARE EXPRESSED IN TWO DIFFERENT TYPES OF MAMMALIAN PERIPHERAL TASTE RECEPTOR CELLS: Type II and Type III cells. Type II cells lack voltage-gated calcium channels (VGCCs) and chemical synapses. In these cells, ryanodine receptors contribute to the taste-evoked calcium signals that are initiated by opening inositol trisphosphate receptors located on internal calcium stores. In Type III cells that do have VGCCs and chemical synapses, ryanodine receptors contribute to the depolarization-dependent calcium influx.
  
  
  
  The goal of this study was to establish if there was selectivity in the type of VGCC that is associated with the ryanodine receptor in the Type III taste cells or if the ryanodine receptor opens irrespective of the calcium channels involved. We also wished to determine if the ryanodine receptors and VGCCs require a physical linkage to interact or are simply functionally associated with each other. Using calcium imaging and pharmacological inhibitors, we found that ryanodine receptors are selectively associated with L type VGCCs but likely not through a physical linkage.
  
  
  
  Taste cells are able to undergo calcium induced calcium release through ryanodine receptors to increase the initial calcium influx signal and provide a larger calcium response than would otherwise occur when L type channels are activated in Type III taste cells.
authors.affiliation: Department of Biological Sciences, University at Buffalo, The State University of New York, Buffalo, New York, United States of America.
authors.forename: Michelle R
authors.initials: MR
authors.lastname: Rebello
authors.forename: Amanda B
authors.initials: AB
authors.lastname: Maliphol
authors.forename: Kathryn F
authors.initials: KF
authors.lastname: Medler
mesh_terms: D000818:Animals; D002118:Calcium / Q000378:metabolism; D020746:Calcium Channels, L-Type / Q000378:metabolism*; D002478:Cells, Cultured; D005260:Female; D005968:Glutamate Decarboxylase / Q000235:genetics; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D007150:Immunohistochemistry; D008297:Male; D008564:Membrane Potentials / Q000502:physiology; D008822:Mice, Transgenic; D011401:Promoter Regions, Genetic; D019837:Ryanodine Receptor Calcium Release Channel / Q000378:metabolism*; D013650:Taste Buds / Q000166:cytology / Q000378:metabolism*; D056969:Voltage-Sensitive Dye Imaging
chemical_list: D020746:Calcium Channels, L-Type; D019837:Ryanodine Receptor Calcium Release Channel; D049452:Green Fluorescent Proteins; D005968:Glutamate Decarboxylase; C402565:glutamate decarboxylase 1; D002118:Calcium