Megakaryopoiesis disturbances in atherosclerotic rabbits

Increased Platelet Cholesterol and Decreased Percentage Volume of Platelets as a Secondary Risk Factor for Coronary Artery Disease

“…Tandon et al [13] demonstrated that increased platelet membrane cholesterol doubled the platelet adherence and thrombus size with respect to cholesterol-normal platelets in perfusion studies. It is also observed that platelets produced from the megakaryocytes of rabbits fed with a high cholesterol diet are small-er than controls [14] . Stuart et al [15] have shown that cholesterol-enriched platelets converted arachidonic acid to platelet thromboxane B 2 at a higher rate than cholesterol-depleted platelets in vitro.…”

The Activated Megakaryocyte-Platelet-System Vascular Disease: Focus on Diabetes

“…85 During the early atherogenesis of rabbits, megakaryocyte size and ploidy balance are affected. 30 ' 49 We investigated in adult, genetically related BB rats as a model for immunogenic type 1 -like diabetes mellitus at various stages whether the endomitotic ploidy balance and the GPIIb/IIIa expression were altered. In summary, the results strikingly mirror the findings with peripheral platelets from human diabetics on the level of bone marrow megakaryocytes and point the way to an immunologically triggered primary change of megakaryocytic thrombopoiesis and to a possible enhancement of the endomitotic cycle of megakaryocytes under the conditions of exogenous insulin substitution.…”

The megakaryocyte platelet system and vascular disease

“…Some studies have shown that in rabbits and guinea pigs fed a high cholesterol diet the platelet half-life is shortened [70] and the induction of atherosclerotic lesions in the aorta is associated with an increase in megakaryocyte size and platelet count [71,72]. However other workers have shown that the development of early atherosclerotic lesions in animals is associated with a decrease in megakaryocyte size and DNA content [73,74]. This may reflect either an increased influx of committed stem cells or an increased efflux of large megakaryo- cytes in response to platelet demand or as a direct effect of cholesterol.…”