Effect of hypercholesterolaemia on platelet growth factors.
Evidence from several sources suggests that important interactions occur between platelets and low-density lipoproteins. This study was undertaken to find out if diet-induced hypercholesterolaemia affects the growth factor content in circulating platelets. Minipigs were fed either normal diet supplemented with 2% cholesterol (n = 12) or normal diet alone (n = 12). After 4 months, mean platelet volume was significantly lower (P < 0.05) and monocyte count was significantly higher (P < 0.05) in the cholesterol group. Serum and intraplatelet levels of platelet-derived growth factor (BB homodimer) and transforming growth factor beta 1 were statistically unchanged after diet. Hypercholesterolaemia did not affect the proliferative effect of either serum or platelet lysates on porcine vascular smooth muscle cells and Swiss-3T3 cells in culture. A significant positive correlation between Swiss-3T3 and smooth muscle cell proliferation was present in both groups. These results suggest that the atherosclerosis-promoting effect of hypercholesterolaemia cannot be explained by its direct effect on smooth muscle cell proliferation or by changes in serum or intraplatelet concentrations of growth factors.
Department of Cardiology, University Clinic and School of Medicine, Pamplona, Spain.
I
I
García-Bolao
J
J
Merino
A
A
Martínez
A
A
Grau
E
E
Alegría
D
D
Martínez-Caro
D016475:3T3 Cells; D000818:Animals; D001772:Blood Cell Count; D001792:Blood Platelets / Q000737:chemistry*; D006937:Hypercholesterolemia / Q000097:blood*; D008297:Male; D051379:Mice; D010982:Platelet-Derived Growth Factor / Q000032:analysis*; D013552:Swine; D013556:Swine, Miniature; D016212:Transforming Growth Factor beta / Q000097:blood*
D010982:Platelet-Derived Growth Factor; D016212:Transforming Growth Factor beta