THE INFLUENCE OF AGE AND LOCATION OF ARTERIAL LESION ON THE PATHOGENESIS AND DEVELOPMENT OF EARLY ATHEROSCLEROTIC LESIONS IN YOUTH

From 1986 to 1989, 324 aortae from accidental death aged 15-39 were co llected from two locations, one of higher prevalence (Beijing in North China), and the other of lower prevalence (Nanning in South China) of atherosclerosis (AS) and coronary heart disease (CHD). Morphometry an d biochemical analyses, were used in the study with emphasis on the ch anges of smooth muscle cells (SMC) in the aortic intima and on the aor tic proteoglycans (PGs) of specimens from both locations to elucidate their relationship with the pathogenesis and development of AS and to find ways, if any, for the prevention and control of AS. The results s howed that the densities, especially the area density of the cell nucl ei of aortic SMC were significantly higher in specimens from the North than those from the South (P<0.01). Nuclear densities of SMC negative ly correlated with alcian blue-positive substances; both total PGs and Heparin sulfate PG (HSPG, inhibitory to SMC proliferation) of the aor tic intima and media were lower in specimens from the North than those from the South (P<0.01). The percentage of sudanophilic lesion (SL) i n the total intimal area, showing the extent of fatty infiltration of aortae from the two locations, was similar except that of the male abd ominal aortae which was higher in the North (P<0.01). The above findin gs showed that decreased content of HSPG which is inhibitory to SMC pr oliferation might be one of the causes of the augmentation of aortic S MC proliferation in Beijing specimens; and also the increased serum ch olesterol concentration of the population in Nanning was reflected in the SL of the aortic intima. The latter should call our attention to t he prevention of AS or CHD.