LAUSR

A high rate of change in the composition of saliva can be used to monitor biorhythms (seasonal and circadian). Research objective -the study of the dynamics of the near-24-hour mineral composition of saliva in men and women. Methods. The study involved 40 people (20 men, 20 women, age 23.1 ± 0.9 years). Saliva samples were collected every 3 hours during the day. The mineral composition of saliva was defined by the capillary electrophoresis technique. The cross-group differences were evaluated using the non-parametric criterion. Results. It is shown that the sodium concentration reaches its maximum values at night (9.67 mM), and then monotonously decreases to 12-15 p.m. (5.72 mM). For potassium concentration, the maximum is observed around 12 p.m. (10.71 mM), remains at a stably high level until 21 p.m., after which it decreases until 6:00 a.m. in the morning (8.78 mM). For the Na/K ratio, one maximum is observed, corresponding to 3 a.m. in the night (Na/K = 1.257), and one minimum at 12-13 p.m. (Na/K = 0.666; р = 0.0082). Conclusion. Thus, the diurnal dynamics of the parameters studied is characterized by pronounced periodicity. The revealed regularities are caused by a change in the rate of saliva secretion during the day, and by the action of hormones.