Decline in Plasma Membrane Ca2+-ATPase Activity and Increase in Cytosolic-Free Ca2+ Concentration of Endotoxin-Injected Mice Livers

• Published in: Biological & pharmaceutical bulletin Vol. 16; no. 8; pp. 808 - 810
• Main Authors: SAKAGUCHI, Shuhei, TSUTSUMI, Eiji, YOKOTA, Katsushi
• Format: Journal Article
• Language: English
• Published: Tokyo The Pharmaceutical Society of Japan 1993; Maruzen; Japan Science and Technology Agency
• Subjects: [Ca2+]i in liver cell; Bacterial diseases; Biological and medical sciences; Ca2+-ATPase activity; endotoxin; Experimental bacterial diseases and models; Infectious diseases; liver plasma membrane damage; Medical sciences; Enzyme; Rodentia; Hepatic disease; Endotoxin; transporting ATPase; Vertebrata; Mammalia; Enzymatic activity; Mouse; Animal; Plasma membrane; Digestive diseases; Hydrolases; Intracellular; Ca; Endotoxemia
• ISSN: 0918-6158; 1347-5215
• DOI: 10.1248/bpb.16.808

The present study describes the activity of Ca2+-ATPase in liver plasma membrane and cytosolic-free Ca2+ concentration ([Ca2+]i) in an individual vital cell in mouse liver 18h after endotoxin administration. Ca2+-ATPase activity in liver plasma membrane in the poisoned mice was markedly decreased to 28% of that in the control. The membrane protein damage in liver was found mostly in the molecular weight (M.W.) regions near 60000-150000 in endotoxemic mice, and was markedly injured near 140000 (M. W. of Ca2+-ATPase in liver plasma membrane). The level of [Ca2+]i in liver cells in endotoxin-poisoned mice was greater at 18h postintoxication than that of the control.These findings suggest the possibility that the depression of Ca2+-ATPase activity in liver plasma membrane in mice may contribute to membrane damage caused by the endotoxin, and that the increase of [Ca2+]i in liver cytoplasm may partially explain various endotoxin-induced metabolic disorders.