Age-related influence of piracetam on mitotic index and number of silver-stained nucleolus organizer regions.

Mitotic indices and the number of silver-positive nucleolus organizer regions (AgNORs) were scored in phytohemagglutinin-stimulated cultures of peripheral lymphocytes from two age groups of females (mean = 23.1 and 84.0 yr, respectively) under the influence of Piracetam (2-oxo-pyrrolidine-1-acetamid; Nootropil, Reg. No. 17051) and in simultaneously set up control cultures without Piracetam addition. Piracetam concentrations of 10, 14 and 16 mg/ml culture medium produced a highly significant, decreasing effect on both parameters tested, without an age-related difference. Lower Piracetam concentrations (2 and 4 mg/ml culture medium) showed a depressant effect on some of the cultures only; but, on average, there was a rather equal, significant, dose-dependent, linear decrease of the mitotic indices of both age groups, whereas the suppressive effect on the number of AgNORs was significant in cultures from the young females only.