R. De Crom et al., Irradiated versus nonirradiated endothelial cells: Effect on proliferationof vascular smooth muscle cells, J VAS INT R, 12(7), 2001, pp. 855-861
PURPOSE: Endovascular radiation therapy is a promising strategy for the pre
vention of restenosis. Radiation prevents proliferation of vascular smooth
muscle cells, thereby reducing the incidence of restenosis, but may also af
fect the remaining endothelial cells. For this reason, a comparison was mad
e between irradiated and nonirradiated endothelial cells and their effects
on the proliferation of vascular smooth muscle cells in a coculture system
was evaluated.
MATERIALS AND METHODS: A coculture system was used, in which both endotheli
al cells and vascular smooth muscle cells were grown on opposite sides of a
semipermeable membrane. After a period of growth arrest, the proliferation
of vascular smooth muscle cells was measured during four subsequent days.
RESULTS: The presence of endothelial cells stimulated the proliferation of
vascular smooth muscle cells during the first days of analysis but had an i
nhibitory effect during the subsequent days (P < .5). gamma -irradiation of
endothelial cells resulted in a complete blockage of the proliferation of
these cells. However, irradiated endothelial cells affected the proliferati
on of: vascular smooth muscle tells in coculture in a fashion comparable to
nonirradiated endothelial cells (P > .5).
CONCLUSION: The results suggest that, in endovascular radiation therapy, ir
radiation of endothelial cells does not change their effects on the prolife
rative behavior of vascular smooth muscle cells.