DECLINING DENSITY OF INTIMAL SMOOTH-MUSCLE CELLS AS A PRECONDITION FOR ATHERONECROSIS IN THE CORONARY-ARTERY

As arteries move from a healthy youth toward the atheronecrotic state of later life, they maintain a record which can be read by measuring t he declining densities of intimal smooth muscle cells. Atheronecrosis is found when the artery is marked by expanded collagenous matrix, whi ch dilutes the resident smooth muscle cells to a critically low cell d ensity. Aging produces atheronecrosis through effects that are associa ted with diminishing cell density, without need to consider any other mechanism. Male-female differences in atheronecrosis could, in a stati stical sense, be fully explained by a faster decline of cell density i n men. Arteries with low cell densities foster inception of atheroscle rotic ''plaques'' when they are focally infiltrated by collections of foam cells. These findings emerge from morphometric assessment of hema toxylin and eosin stained paraffin sections of coronary arteries obtai ned at autopsy in a series of forensic cases.