Figure 1.

Caveolin and eNOS expression in endothelial cells exposed to normocholesterolemic and hypercholesterolemic human serum. (a) Mean (± SEM, n = 10) cholesterol concentrations of human plasma fractions divided into three categories and used in the experiments discussed below. Hatched areas correspond to LDL-C as a fraction of total plasma cholesterol. (b) Caveolin (top) and eNOS (bottom) immunoblots from endothelial cells exposed to the corresponding fractions of human plasma. This experiment was repeated four times with equivalent results. (c) The caveolin immunoblots from endothelial cells exposed to NC or HC serum in the presence or absence of the cysteine protease inhibitor ALLN (25 μM). This experiment was repeated two times with equivalent results. ALLN, N-acetyl-leu-leu-norleucinal; eNOS,endothelial nitric oxide synthase; HC, hypercholesterolemic; IC, intermediate; LDL-C, low-density lipoprotein cholesterol; NC, normocholesterolemic.