Polyunsaturated fatty acids inhibit Mg2+ -ATPase in basolateral membranes from rat enterocytes.
It is known that certain polyunsaturated fatty acids of the n-6 family, for example linoleic and arachidonic acids, can activate both Na+, K+-ATPase and Ca2+-ATPase. These enzymes drive active absorption processes in the duodenal enterocyte. This study presents data which show a 30-50% inhibition of Mg2+-ATPase activity in enterocyte basolateral membrane preparations by linoleic and gamma-linolenic acids (also a member of the n-6 family.) Mg2+-ATPase activity has several possible roles in the enterocyte: involvement in Mg2+ and Ca2+ absorption (as part of Ca2+-ATPase and also myosin I activity) as well as control of phospholipid distribution in the membrane by a class of Mg2+-ATPases called 'flippases'. The action of linoleic and gamma-linolenic acids on basolateral membrane Mg2+-ATPase may thus modulate several cellular transport processes.
Haag
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M
Department of Physiology, University of Pretoria, South Africa. mhaag@medic.up.ac.za
Vermeulen
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Magada
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Kruger
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D000818:Animals; D017301:Ca(2+) Mg(2+)-ATPase / Q000037:antagonists & inhibitors*; D002462:Cell Membrane / Q000201:enzymology; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D005231:Fatty Acids, Unsaturated / Q000494:pharmacology*; D007422:Intestines / Q000201:enzymology*; D007700:Kinetics; D008041:Linoleic Acids / Q000494:pharmacology; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D017965:gamma-Linolenic Acid / Q000494:pharmacology
D004791:Enzyme Inhibitors; D005231:Fatty Acids, Unsaturated; D008041:Linoleic Acids; D017965:gamma-Linolenic Acid; D017301:Ca(2+) Mg(2+)-ATPase