Response of cytosolic calcium to anoxia and cyanide in cultured glomus cells of newborn rabbit carotid body.
Microscopic fluorometry was used to examine the effects of anoxia and cyanide (CN-) on cytosolic calcium [Ca2+]i of cultured carotid body (CB) glomus cells from newborn rabbits. Applications of high K+ and veratridine (VRT), a sodium channel activator, induced rapid and marked increases in [Ca2+]i. These effects were inhibited by D600 a calcium channel blocker. [Ca2+]i changes induced by VRT were also blocked by tetrodotoxin (TTX). Glomus cells exhibited a slow increase in [Ca2+]i in response to anoxia and CN-, and a slight decrease during hyperoxia. The effects of anoxia and CN- were blocked by D600 but not by TTX. We conclude that these stimuli induce calcium entry into glomus cells via voltage-dependent Ca2+ channels. Voltage-dependent Na+ channels were not involved.
Sato
M
M
Department of Physiology, Akita University School of Medicine, Japan.
Ikeda
K
K
Yoshizaki
K
K
Koyano
H
H
D000818:Animals; D000831:Animals, Newborn; D002118:Calcium / Q000378:metabolism*; D002344:Carotid Body / Q000187:drug effects / Q000378:metabolism*; D002478:Cells, Cultured; D003486:Cyanides / Q000494:pharmacology*; D003600:Cytosol / Q000378:metabolism*; D005711:Gallopamil / Q000494:pharmacology; D000860:Hypoxia / Q000378:metabolism*; D011817:Rabbits; D013779:Tetrodotoxin / Q000494:pharmacology; D014701:Veratridine / Q000494:pharmacology
D003486:Cyanides; D005711:Gallopamil; D013779:Tetrodotoxin; D014701:Veratridine; D002118:Calcium