TY - JOUR
T1 - Cytosolic free magnesium, ATP, and blebbing during chemical hypoxia in cultured rat hepatocytes
AU - Harman, Andrew W.
AU - Nieminen, Anna Liisa
AU - Lemasters, John J.
AU - Herman, Brian
N1 - Funding Information:
r This work was supported by Grants AGO7218 and DK30874 from the National Institutes of Health, the Gustavas and Louise Pfeiffer Foundation, and Grant J-1433 from the Office of Naval Research.
PY - 1990/7/31
Y1 - 1990/7/31
N2 - Cytosolic free Mg2+ concentration was determined in 1-day cultured rat hepatocytes using Multiparameter Digitized Video Microscopy (MDVM) of the fluorescent probe, magfura-2. Chemical hypoxia with KCN (5 mM) and iodoacetate (1 mM), a model which mimics the ATP depletion and reductive stress of hypoxia, caused a rapid increase of free Mg2+ from 1.1 ± 0.2 to 1.6 ± 0.2 mM within 4 min. Concurrently, numerous small plasma membrane blebs formed and ATP levels dropped from 13.24 to 1.32 nmol/106 cells. Removal of KCN and iodoacetate resulted in recovery of ATP to 60-70% of pre-exposure levels, a concomitant decrease in cytosolic free Mg2+ back toward basal levels, and reversal of blebbing (bleb resorption). These results indicate that changes of cytosolic free Mg2+ inversely reflect changes of ATP in a model of hypoxia and reoxygenation. Bleb formation and resorption were dependent on the fall and rise of ATP.
AB - Cytosolic free Mg2+ concentration was determined in 1-day cultured rat hepatocytes using Multiparameter Digitized Video Microscopy (MDVM) of the fluorescent probe, magfura-2. Chemical hypoxia with KCN (5 mM) and iodoacetate (1 mM), a model which mimics the ATP depletion and reductive stress of hypoxia, caused a rapid increase of free Mg2+ from 1.1 ± 0.2 to 1.6 ± 0.2 mM within 4 min. Concurrently, numerous small plasma membrane blebs formed and ATP levels dropped from 13.24 to 1.32 nmol/106 cells. Removal of KCN and iodoacetate resulted in recovery of ATP to 60-70% of pre-exposure levels, a concomitant decrease in cytosolic free Mg2+ back toward basal levels, and reversal of blebbing (bleb resorption). These results indicate that changes of cytosolic free Mg2+ inversely reflect changes of ATP in a model of hypoxia and reoxygenation. Bleb formation and resorption were dependent on the fall and rise of ATP.
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U2 - 10.1016/0006-291X(90)92116-H
DO - 10.1016/0006-291X(90)92116-H
M3 - Article
C2 - 2383254
AN - SCOPUS:0024993064
SN - 0006-291X
VL - 170
SP - 477
EP - 483
JO - Biochemical and Biophysical Research Communications
JF - Biochemical and Biophysical Research Communications
IS - 2
ER -