Diphenylene iodonium blocks K+ and Ca2+ currents in type I cells isolated from the neonatal rat carotid body.
Diphenylene iodonium (DPI), an inhibitor of NAD(P)H oxidase, blocks hypoxic excitation of the carotid body. We used the whole-cell patch-clamp technique to investigate the actions of DPI on ionic currents in isolated type I carotid body cells. DPI (10 microM) caused reversible blockade of K+ and Ca2+ currents in these cells, indicating that DPI is a non-selective ion channel blocker. Since hypoxic excitation of the carotid body is dependent on Ca2+ influx into type I cells, our observation that DPI blocks Ca2+ currents in type I cells can account for the ability of this compound to inhibit hypoxic excitation of the intact organ.
Wyatt
C N
CN
Department of Pharmacology, Leeds University, UK.
Weir
E K
EK
Peers
C
C
D000818:Animals; D000831:Animals, Newborn / Q000378:metabolism*; D001713:Biphenyl Compounds / Q000494:pharmacology*; D002121:Calcium Channel Blockers / Q000494:pharmacology*; D015220:Calcium Channels / Q000187:drug effects / Q000378:metabolism; D002344:Carotid Body / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D008564:Membrane Potentials / Q000187:drug effects; D009474:Neurons / Q000187:drug effects / Q000378:metabolism*; D009861:Onium Compounds / Q000494:pharmacology*; D015221:Potassium Channels / Q000187:drug effects*; D051381:Rats
D001713:Biphenyl Compounds; D002121:Calcium Channel Blockers; D015220:Calcium Channels; D009861:Onium Compounds; D015221:Potassium Channels; C031291:diphenyliodonium