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PubMed · 2844608

Insulin-induced decrease in 5'-nucleotidase activity in skeletal muscle membranes.

A Klip·T Ramlal·A G Douen·E Burdett·D Young·G D Cartee·J O Holloszy
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Abstract

Insulin releases inositol phosphoglycans from myocytes in culture [(1986) Science 233, 967-972], which display insulinomimetic activity. Because 5'-nucleotidase is anchored to the membrane through inositol-containing phospholipid glycans, we investigated whether insulin could release the enzyme from the membrane. Membranes prepared from hindquarter muscles of rats perfused with insulin showed a 23% decrease in 5'-nucleotidase activity. Isolated membranes from muscle exposed to insulin in vitro also showed a small but reproducible decrease (9%) in 5'-nucleotidase activity relative to unexposed controls. Phospholipase C from Staphylococcus aureus released 60% of the membrane-bound 5'-nucleotidase. We propose that insulin may activate an endogenous phospholipase C that cleaves phospholipid-glycan-anchored proteins.

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5'-NucleotidaseAnimalsCa(2+) Mg(2+)-ATPaseCell MembraneInsulinMaleMusclesNucleotidasesRatsRats, Inbred StrainsStaphylococcus aureusType C PhospholipasesJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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A Klip, T Ramlal, A G Douen, E Burdett, D Young, G D Cartee, J O Holloszy. 1988-10-10. Insulin-induced decrease in 5'-nucleotidase activity in skeletal muscle membranes.. https://doi.org/10.1016/0014-5793(88)80524-6

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