Biochemistry of Submarine and Diving Stress: II. The Effect of Chronic Hypercapnia on Blood Phosphofructokinase Activity and the Adenine Nucleotide System

摘要

Phosphofructokinase activity and adenine nucleotide levels were determined in blood of guinea pigs exposed to 15% CO2 in 21% O2, balance N2 for varying periods of time up to one week. Acute exposure produced a decrease in enzyme activity while the chronic phase increased activity without attainment of control values. These alterations in blood phosphofructokinase activity strikingly paralleled the biphasic changes in blood pH during acute and chronic hypercapnia. These findings demonstrate that blood phosphofructokinase activity is capable of responding to 'in vivo' fluctuations in blood pH. ATP, ADP, AMP, and the energy charge were virtually unchanged during both phases indicating that hypercapnia is characterized by conservation of high-energy phosphates. (Author)