Tetraethylammonium-induced calcium concentration changes in skin fibroblasts from patients with Alzheimer disease.
Potassium (K+) channel dysfunction in fibroblasts was recently proposed as a potential diagnostic marker for Alzheimer disease (AD). We utilized a microspectrofluorometric method with Fura-2AM to measure intracellular free calcium ([Ca2+]i) following depolarization with the K+ channel blocker tetraethylammonium (TEA) in seven AD and seven control fibroblast cultures. Contrary to our expectation, 43% of the AD and 36% of the control fibroblast plated coverglasses responded with an increase in [Ca2+]i on addition of 100 mM TEA. The data suggest that the TEA-elicited [Ca2+]i response is not a useful AD screening test.
Matsuyama
S S
SS
Psychogeriatric Laboratory (B151R), West LA VAMC, Los Angeles, CA 90073, USA.
Yamaguchi
D T
DT
Vergara
Y
Y
Jarvik
L F
LF
D000328:Adult; D017668:Age of Onset; D000368:Aged; D000544:Alzheimer Disease / Q000175:diagnosis*; D002118:Calcium / Q000378:metabolism*; D002478:Cells, Cultured; D005260:Female; D005347:Fibroblasts / Q000187:drug effects* / Q000378:metabolism; D006801:Humans; D008297:Male; D008875:Middle Aged; D015221:Potassium Channels / Q000187:drug effects; D012867:Skin / Q000473:pathology; D019789:Tetraethylammonium; D013757:Tetraethylammonium Compounds / Q000494:pharmacology*
D015221:Potassium Channels; D013757:Tetraethylammonium Compounds; D019789:Tetraethylammonium; D002118:Calcium