Blood respiratory properties of rainbow trout (Salmo gairdneri) kept in water of high CO2 tension.
1. Blood O2 transport and acid-base balance were studied at 20 degrees C in rainbow trout (Salmo gairdneri) which had been kept in water of high CO2 content (15 mmHg) for at least a week. Also the blood gas chemistry of fish rapidly entering or leaving the hypercapnic environment was studied. 2. Fish entering high CO2 water suffered a sharp decrease in blood pH which significantly reduced O2 transport by the blood, but after a few hours considerable compensation was achieved. 3. After at least a week in high CO2 water, trout showed elevated plasma bicarbonate and PCO2 levels, and a decrease in plasma chloride, while pH was about 0 - 1 pH unit below the level for control fish. Oxygen transport by the blood was marginally reduced. 4. Hypercapnic fish rapidly entering fresh water showed a sharp increase in blood pH and a decrease in blood PO2. These parameters regained normal values after a few hours but plasma bicarbonate and chloride levels took much longer to regain control concentrations. 5. Acid-base balance in hypercapnic fish is discussed with particular reference to the role of the branchial ion exchanges.
D000222:Adaptation, Physiological; D000818:Animals; D001639:Bicarbonates / Q000097:blood; D002245:Carbon Dioxide / Q000097:blood / Q000494:pharmacology*; D006454:Hemoglobins / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D010100:Oxygen / Q000097:blood; D012487:Salmonidae / Q000097:blood*; D013997:Time Factors; D014337:Trout / Q000097:blood*; D014867:Water
D001639:Bicarbonates; D006454:Hemoglobins; D014867:Water; D002245:Carbon Dioxide; D010100:Oxygen