Lipoprotein lipase (LpL) on the surface of cardiomyocytes increases lipid uptake and produces a cardiomyopathy
J. Clin. Invest. Hiroaki Yagyu, et al. 111:419 doi:10.1172/JCI16751 [Go to this article.]

Figure 6
(a and b) LpL immunofluorescence in the hearts. An mAb was used to detect hLpL in hearts. In mice with transgenic expression of normal hLpL in the hearts on the homozygous LpL knockout background (He-LpL/LpL0) (28), hLpL was found in the cytoplasm and at the membrane. Hearts from hLpL^GPI/LpL1 mice had intense staining for LpL on the surface of cardiomyocytes. In a, intensity of red staining is amplified tenfold compared with b. (c and d) Myocardial lipid accumulation in 24 h–fasted hLpL^GPI/LpL1 mice. Oil red O staining shows an abundance of neutral lipid droplets within the cardiomyocytes of hLpL^GPI/LpL1 (d) mice compared with LpL1 (c) mice. ×400. (e and f) Electron microscopy. Ultrastructure of LpL1 mouse myocardial tissues exhibited normal morphological features with well-organized myofilaments and mitochondria (e). T tubules are not visible. The hLpL^GPI/LpL1 myocytes appeared severely distorted due to more mitochondria, irregular Z band of myofibrils, and dilated T tubules (f). (g) Northern blot analysis. Ten micrograms of total RNA were isolated from heart and subjected to Northern blot analysis using a part of cDNA encoding PPARα, CPT-1, ACO, ANF, and GLUT4 as probes. GAPDH is shown as a control for loading.