Effects of the endothelium on growth responses in arteries.

Observations in cell culture and during arterial organoid culture indicate that the endothelium may influence arterial wall mass. The endothelium can inhibit and promote stimulation of DNA synthesis in the underlying smooth muscle depending on the experimental conditions, the type of vessel, and the species. The process seems to be altered during neointima formation and in a genetic model of essential hypertension. In these respects, endothelial influences on arterial smooth growth resemble endothelial influences on arterial smooth muscle tone. The mediators that are involved, however, may differ.