The biochemical composition of haemodynamically stressed vascular tissue. Part 1. The lipid, calcium and DNA concentrations in experimental arteriovenous fistulae.

Experimental arteriovenous anastomoses were fashioned between the external jugular vein and the common carotid artery in sheep. The altered haemodynamics induced morphological changes, particularly in the venous tissue. Many of these alterations were similar to those seen in human atherosclerosis. Some of the biochemical compositional changes that occurred in such tissues are reported here. Whilst the serum cholesterol level was unaltered during the post-operative period, there was an increase in the free and total cholesterol content of the experimental vein but not of the artery. The serum triglyceride level approximately doubled but the tissue triglyceride rose on only the arterial side of the shunt. There was a decrease in the triglyceride level in the experimental vein. The calcium content showed a slight decrease in both experimental arterial and venous tissue although the drop was not statistically significant. The DNA concentration which was assayed so as to provide a measure of the cell density was about 1.5-2.0 times higher in the arterial tissue.