Lipoprotein lipase: cellular origin and functional distribution.
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Observations suggest that in some tissues LPL is synthesized by parenchymal cells and spreads along the vascular mesh and transfer to the vascular endothelium is, however, not the only route taken by LPL.Abstract:
Lipoprotein lipase (LPL, E.C. 3.3.1.34) is the enzyme responsible for hydrolysis of triacylglycerols in plasma lipoproteins, making the fatty acids available for use by subjacent tissues. LPL is functional at the surface of endothelial cells, but it is not clear which cells synthesize the enzyme and what its distribution is within tissues and vessels. We have searched for specific cell expression of the LPL gene by in situ hybridization using a RNA probe and for the corresponding protein distribution by immunocytochemistry on cryosections of some LPL-producing tissues of guinea pigs. In white and brown adipose tissues, heart and skeletal muscle, and lactating mammary gland, there was positive hybridization for LPL mRNA over all members of the major cell types, indicating that mature and immature adipocytes, muscle cells, and mammary epithelial cells are main sources of LPL. In large vessels, LPL expression was detected in some smooth muscle cells in the media layer. There was no positive hybridization for LPL mRNA over endothelial cells in any of the tissues studied, but there was immunoreaction for LPL protein at endothelial surfaces of all blood vessels. In the kidney, there was strong immunofluorescence at the vascular endothelium, particularly in the glomeruli, but little or no LPL mRNA was detected in the surrounding cells. These observations suggest that in some tissues LPL is synthesized by parenchymal cells and spreads along the vascular mesh. Transfer to the vascular endothelium is, however, not the only route taken by LPL. In the mammary gland most of the enzyme protein appeared to be secreted, partly in association with milk fat droplets.(ABSTRACT TRUNCATED AT 250 WORDS)read more
Citations
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A definition of initial, fatty streak, and intermediate lesions of atherosclerosis. A report from the Committee on Vascular Lesions of the Council on Arteriosclerosis, American Heart Association.
H. C. Stary,A. B. Chandler,S. Glagov,John R. Guyton,W Insull,M. E. Rosenfeld,S A Schaffer,C. J. Schwartz,W. D. Wagner,R. W. Wissler +9 more
TL;DR: The compositions of lesion types that precede and that may initiate the development of advanced atherosclerotic lesions are described and the possible mechanisms of their development are reviewed.
Journal ArticleDOI
A definition of initial, fatty streak, and intermediate lesions of atherosclerosis. A report from the Committee on Vascular Lesions of the Council on Arteriosclerosis, American Heart Association.
H. C. Stary,A. B. Chandler,S. Glagov,John R. Guyton,W Insull,M. E. Rosenfeld,S A Schaffer,C. J. Schwartz,W. D. Wagner,R. W. Wissler +9 more
TL;DR: The compositions of lesion types that precede and that may initiate the development of advanced atherosclerotic lesions are described and the possible mechanisms of their development are reviewed.
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Lipoprotein lipase: structure, function, regulation, and role in disease
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Role of changes in cardiac metabolism in development of diabetic cardiomyopathy
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Physiological regulation of lipoprotein lipase.
TL;DR: It is now evident that most of the physiological variation in LPL activity, such as during fasting and exercise, appears to be driven via post-translational mechanisms by extracellular proteins.
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Molecular cloning and sequence analysis of cDNA encoding lipoprotein lipase of guinea pig.
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TL;DR: Analysis of genomic DNA by Southern blotting indicated a single gene locus coding for lipoprotein lipase seems to be involved in the production of the various mRNAs.