Endothelium-dependent responses and their potential relevance to the distribution of blood flow during hemorrhagic shock.

The endothelium releases vasoactive substances in response to several circulating hormones and to changes in shear stress of the flowing blood across the endothelial surface. Because the distribution of receptors mediating the release of endothelium-derived factors is not uniform along the vascular bed, the vascular endothelium has a potential role in regulating regional blood flow and maintaining peripheral resistance during the course and recovery from hemorrhagic shock.