Circadian rhythmicity of polyamine urinary excretion.

Polyamines are small, highly charged, organic cations of possible regulatory importance in RNA-dependent protein synthesis, the production of which reflects cellular growth and division. The cytokinetics of normal cell populations is circadian rhythmic. This is reflected by a circadian rhythmicity undescribed previously in urinary monoacetylputrescine and the ratio of N1-acetylspermidine to N8-acetylspermidine in healthy individuals. Patients harboring advanced cancers sometimes excrete abnormal quantities of certain acetylated polyamines, and their urine samples may exhibit an abnormally high ratio of N1-acetylspermidine to N8-acetylspermidine. Changes in polyamine production and excretion associated with cancer may be best perceived by rhythmometric analysis of carefully timed samplings.