Intimal cell mass-derived atherosclerotic lesions in the abdominal aorta of hyperlipidemic swine Part 1. Cell of origin, cell divisions and cell losses in first 90 days on diet☆

摘要: Abstract Atherosclerotic lesions may originate and develop in a variety of ways. In this study we are focusing our attention on atherosclerotic arising normally occurring intimal cell masses (ICM) the abdominal aortas hyperlipidemic (HL) swine. Times chosen for were 0, 14, 49 90 days HL diet; mash-fed swine used as controls. Total numbers cells ICM mash similar at 14 days; by number had increased dramatically to 8-fold greater than control values. Changes present thus preceding increase included extensive intracellular lipid accumulation with count nearly half involved elevated tritiated thymidine labeling indices (LI) 4-fold control. Differential counts transmission electron microscopy made days. More 95% all smooth muscle (SMC), relatively few monocytes being present. Calculations from LI total showed that entire could be accounted divisions among resident SMC ICM. Further calculations suggested losses (deaths) minimal. Scanning studies reported elsewhere revealed no loss endothelial integrity. The results suggest: (1) arise stimulation hyperplastic activity, (2) role early development these is minimal if any, (3) view intact endothelium platelets not likely play an important role, (4) death major factor, (5) most candidate growth stimulatory (? mitogen) some component(s) excess accumulates