ATP and integrity of human red blood cells

In spite of the well known significance of ATP in the energy dependent life processes, the role of ATP in maintaining cellular integrity is poorly und erstood. A possible model for studying ATP dependent life processes is to m onitor the kinetics of changes seen intra/extracellularly during ATP deplet ion. In our model system anticoagulated human whole blood was incubated at different temperatures to reduce intracellular ATP without addition of any chemicals. The red blood cells in their own plasma were incubated for sever al days at 4 degrees C or at 37 degrees C, and ATP, glucose, K+, Na+, hemog lobin, water content, mean corpuscular volume (MCV), pH and Ca2+ were analy zed in time-sequences. All the examined parameters remained practically unc hanged at 4 degrees C, while at 37 degrees C total ATP and glucose decrease d parallel and after a transient increase of MCV, the water content of red blood cells decreased. As the actual ATP fell below 10% of the initial ATP content (at 48 h), the release of potassium sharply increased. Release of h emoglobin started only after 96 hours of incubation. Maximums of changes of the examined parameters were found at different time intervals. The maxima l speed of concentration changes for glucose was found at 12-24 hours of in cubation and at 24-36 hours for ATP, at 48-60 hours for K+-Na+ and after 96 hours for hemoglobin.