[Age-specific features of the cyclic nucleotide system in children]

The content of cyclic nucleotides (cAMP and cGMP) in the plasma and peripheral blood leukocytes, levels of their daily urinary excretion, and the activities of adenylate cyclase and cAMP-dependent phosphodiesterase responsible for the synthesis and degradation of cAMP in the leukocytes were studied in 114 healthy children aged 0 to 15 years. The levels of cyclic nucleotides in the blood plasma and leukocytes were found to gradually increase with age, as well as urinary excretion of cAMP. Both cAMP synthesis and degradation were found intensified with age. The detected age-specific features of cyclic nucleotides are important criteria for the assessment of the development of children and their health status. The findings may be used as reference values in assessment of the status of cyclic nucleotides in children with various diseases.