Alterations in intracellular calcium transients of fibroblasts from progressive systemic sclerotic patients: a digital imaging microscopic study.
Intracellular Ca2+ concentrations ([Ca2+]i) in cultured skin fibroblasts from normal subjects and progressive systemic sclerosis (PSS) patients were determined by using Fura-2 and fluorescent videomicroscopy. With the exception of fibroblasts from one PSS patient showing a higher [Ca2+]i, no significant difference was observed in resting [Ca2+]i between the two groups of fibroblasts. Bradykinin (BK) (10 microM) induced a transient [Ca2+]i increase in normal fibroblasts, whereas the BK-induced [Ca2+]i increase was reduced or not detectable in PSS fibroblasts. Removal of extracellular Ca2+ did not eliminate the BK-induced [Ca2+]i increase in normal fibroblasts. These findings suggest that BK stimulates Ca2+ release from intracellular stores in human fibroblasts, and also that the BK-mediated Ca2+ release is impaired in PSS fibroblasts.
Seishima
M
M
Department of Dermatology, Gifu University School of Medicine, Japan.
Kudo
Y
Y
Nagao
S
S
Mori
S
S
Nozawa
Y
Y
D000328:Adult; D001920:Bradykinin / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism*; D005260:Female; D005347:Fibroblasts / Q000187:drug effects / Q000378:metabolism* / Q000473:pathology; D016257:Fura-2; D006801:Humans; D008297:Male; D008856:Microscopy, Fluorescence / Q000379:methods; D008875:Middle Aged; D012595:Scleroderma, Systemic / Q000378:metabolism* / Q000473:pathology
D001920:Bradykinin; D002118:Calcium; D016257:Fura-2