Ca2+ Channel Currents in Type I Carotid Body Cells from Normoxic and Chronically Hypoxic Rats

E. Carpenter, C. N. Wyatt, C. J. Hatton, D. Bee, C. Peers

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

Rats born and reared under chronically hypoxic (10% O2) conditions do not respond to acute hypoxia with an increased ventilation. Their carotid bodies undergo hyperplasia and hypertrophy and we have recently shown that K+ channels recorded in type I carotid body cells isolated from normal and chronically hypoxic (CH) rats show marked differences (Wyatt et al, 1995): normoxic type I cells express Ca2+-activated K+ (KCa) channels which are inhibited by acute hypoxia, leading to cell depolarization, opening of voltagegated Ca2+ channels (VGCCs) and the consequent influx of Ca2+ to trigger neurotransmitter release (Peers & Buckler, 1995). In type I cells from CH rats, there is far less expression of KCa channels, and, whilst the remaining K+ channels are inhibited by hypoxia, this does not lead to cell depolarization, which may explain the lack of ventilatory response to acutely inspired hypoxia in intact CH rats (Wyatt et al, 1995). An important factor in the response of normal type I cells to hypoxia is the activation of VGCCs, of which numerous sub-types exist in various tissues. It is known that L-type VGCCs are involved in hypoxic chemotransduction (Buckler & Vaughan-Jones, 1994), but very little is known about the possible presence of other VGCCs, whether they may be involved in chemotransduction, and whether they are affected by chronic hypoxia. We have therefore compared the properties of VGCCs in type I carotid body cells isolated from normoxically-reared and CH rats.
Original languageEnglish
Title of host publicationFrontiers in Arterial Chemoreception
EditorsPatricio Zapata, Carlos Eyzaguirre, Robert W. Torrance
PublisherSpringer New York
Pages105-108
Number of pages4
Volume410
ISBN (Electronic)978-1-4615-5891-0
ISBN (Print)978-0-306-45490-5, 978-1-4613-7702-3
DOIs
StatePublished - 1996
Event13th International Symposium on Arterial Chemoreceptors - Santiago, Chile
Duration: Mar 25 1996Mar 29 1996

Publication series

NameAdvances in Experimental Medicine and Biology
ISSN (Print)0065-2598

Conference

Conference13th International Symposium on Arterial Chemoreceptors
Country/TerritoryChile
CitySantiago
Period3/25/963/29/96

ASJC Scopus Subject Areas

  • General Biochemistry,Genetics and Molecular Biology

Keywords

  • Calcium/*metabolism
  • Calcium Channels/*metabolism
  • Carotid Body/*metabolism
  • Hypoxia/*metabolism
  • Nerve Tissue Proteins/*metabolism
  • 3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethyl-5-nitro-4-(2-(trifluoromethyl)phenyl)-, Methyl ester/pharmacology
  • ; Action Potentials/drug effects
  • Animals
  • Calcium Channel Blockers/pharmacology
  • Calcium Channels/classification
  • Calcium Channels/drug effects
  • Calcium Channels, L-Type
  • Carotid Body/drug effects
  • Carotid Body/pathology
  • Cell Hypoxia
  • Cells, Cultured
  • Chronic Disease
  • Hypoxia/congenital
  • Ion Transport/drug effects
  • Nerve Tissue Proteins/drug effects
  • Nifedipine/pharmacology
  • Peptides/pharmacology
  • Rats
  • omega-Conotoxin GVIA

Disciplines

  • Molecular and Cellular Neuroscience
  • Medical Neurobiology
  • Neurosciences

Cite this