Time-dependent loss of adenosine 5'-monophosphate deaminase activity may explain elevated adenosine 5'-triphosphate levels in senescent erythrocytes.
Senescent erythrocytes from rabbits were previously shown to have elevated levels of adenine nucleotides. The present study documents that aged red blood cells have a normal synthetic capacity for adenine nucleotides, as indicated by normal levels of adenosine kinase. However, senescent erythrocytes do have decreased levels of adenosine 5'-monophosphate deaminase, the critical enzyme involved in degrading adenine nucleotides. These circumstances of a normal synthetic capacity in the presence of decreased catabolic ability were observed previously in a human genetic deficiency of adenosine 5'-monophosphate deaminase; the red blood cells in these patients accumulate adenosine 5'-triphosphate as do senescent erythrocytes in rabbits.
Dale
G L
GL
Department of Molecular and Experimental Medicine, Research Institute of Scripps Clinic, La Jolla, CA 92037.
Norenberg
S L
SL
D000659:AMP Deaminase / Q000097:blood*; D000248:Adenosine Kinase / Q000097:blood; D000255:Adenosine Triphosphate / Q000097:blood*; D000818:Animals; D004905:Erythrocyte Aging; D009709:Nucleotide Deaminases / Q000097:blood*; D011817:Rabbits; D013997:Time Factors
D000255:Adenosine Triphosphate; D000248:Adenosine Kinase; D009709:Nucleotide Deaminases; D000659:AMP Deaminase