Effect of endothelial cells and transforming growth factor-beta 1 on cultured vascular smooth muscle cell growth...

Smooth muscle cells (SMCs) cultured alone exhibit characteristic "hill and valley" macroscopic growth features. We studied smooth muscle cells cocultured with endothelial cells and the effect of transforming growth factor beta 1 on smooth muscle cells: Bovine smooth muscle cells were plated on 13 microns-thick semipermeable membranes. Smooth muscle cells were cultured either alone (in Dulbecco's Modified Eagles Media/2.5% calf serum, four wells/group); with neutralizing anti-transforming growth factor-beta 1 antibody (10 micrograms/ml); with the protease inhibitor aprotinin (prevents plasmin-mediated activation of transforming growth factor-beta 1, 200 mg/ml); or in the presence of confluent bovine endothelial cells cocultured on the opposite side of the membrane before plating smooth muscle cells. After 72 hours in culture smooth muscle cell organizational growth characteristics were examined by light microscopy. Hill and valley formation by smooth muscle cells resulted in areas of the membrane becoming devoid of smooth muscle cells, whereas other areas developed multilayered densely populated smooth muscle cells. Computed planimetry was used to measure this bare surface area to quantitate the extent of hill and valley growth, which was compared between groups by analysis of variance. Smooth muscle cells cultured alone demonstrated prominent hill and valley formation with a bare surface area of 2.64 +/- 0.51 mm2. Smooth muscle cells exposed to transforming growth factor-beta 1 antibody had much less hill and valley formation (bare surface area 0.92 +/- 0.29, p < 0.01), whereas aprotinin virtually prevented hill and valley formation (bare surface area 0.0, p < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)