ISSN:
1432-136X
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Medicine
Notes:
Summary 1. The respiration ofOctopus vulgaris was investigated, particular attention being given to the role of the blood in the uptake and transport of oxygen. Measurements were made on free moving animals. Oxygen consumption was recorded and blood sampled with indwelling cannulae in pre and post branchial (aortic) vessels. 2. In normoxia the mean values for circulating bloodP O 2 are 78.1±2.9 mmHg for arterial and 30.0±3.2 mmHg for venous blood. The hemocyanin in arterial blood is 98% saturated and 14% saturated in venous blood. There is a 0.11 pH unit decrease between arterial and venous blood. 3. The in vitro Bohr coefficient has a value of −1.58 Δlog10 P 50/Δ pH. 4. In hypoxia the oxygen consumption declined markedly below an ambientP O 2 of 90 mmHg. 5. Hypoxia was accompanied by a decline in aorticP O 2 but a near mainstenance of arterial hemocyanin saturation so that the arterial to venous difference declined by only 17% between normoxia and the most acute hypoxia. A marked increase in hemocyanin oxygen affinity occurred with a rise in blood pH. The large Bohr factor of the blood may be a major adaptation to hypoxic conditions, while bradycardia and modulations of stroke volume may play only a small part.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00688885
