VOLUME–PRESSURE RELATIONSHIPS OF THE TURKEY AORTA

Abstract

This experiment was an attempt to define the volume–pressure relationships of the untreated turkey aorta and to evaluate the effect on these relationships of treatment with beta-aminopropionitrile (BAPN) and ascorbic acid. Distensibility values (ΔV/ΔP) were calculated for each of three linear segments of the volume–pressure curve for treated and untreated thoracic and abdominal aortas. In general, the distensibility of the thoracic aorta was greater than that of the abdominal aorta. In both aortic segments addition of BAPN to the ration tended to increase, whereas the addition of ascorbic acid tended to decrease distensibility. The volume–pressure curve of the thoracic aorta was sigmoid in nature and demonstrated the greatest distensibility in the normal physiological systolic blood pressure range of the male Broad Breasted Bronze turkey. Both aortic segments exhibited hysteresis and an isobaric volume change upon successive loading. These phenomena decreased in magnitude with successive loadings.