Basement Membrane of Smooth Muscle Cell and Its Association With Elastic Tissue in Aorta
Organization and connection between smooth muscle cells and elastic tissues in aortas is not elucidated. Keech believed that the smooth muscle cells anchore on the elastic tissue. Among the fibers of the aortic connective tissue, there are collagen, elastic tissue and microfibril. This communication is to present evidence that the microfibrils which are derived from the basement membrane of the smooth muscle cells, play a role for connection between the smooth muscle cells and the elastic tissues.Thoracic aortas from new born rats were fixed with Dalton's chrom-osmium solution, embedded in Epon 812 and stained with uranyl acetate and lead citrate. Our previous work showed that the smooth muscle cell synthesized the elastic tissue during its differentiation prior to completing the process. At the actively synthesizing site of the cell, the basement membrane was replaced by numerous microfibrils (Fig. 1 MF). The microfibrils extended from the basement membrane toward the preformed elastic lamellae (EL), occasionally surrounded scallop-shaped elastic unit (EU).