The results of experimental studies on puberal male rats in studying chronopharmacological peculiarities of mildronate influence («Grindex» JSC, Latvia) on the indices of the excretory renal function have been described. Mildronate (50 mg/kg) was injected intraperitoneally in different periods of the day (800, 1200, 1600, 2000, 2400, 0400) on the background of water loading (5% of the body weight, per os). The urine was collected during the day every 2 hours and the indices of diuresis, excretion of ions of sodium, potassium, creatinine and protein were analyzed. Mildronate has been found to have a slight diuretic and more expressed saluretic action, which showed dependence on the time of injecting the medicine. The indices of the excretory function of the kidneys are more expressed when injecting in the daytime (800, 1200, 1600). In addition to the increase of the amplitude of circadian biorhythms the diurnal mean value of natriuresis increased 1.6 times, potassium uresis – 1.2 times. The acrophase of sodium ions excretion occurs in the period from 1200 to1400 p.m., while natriuresis increases 2.6 times comparing to the indices of the experemental animals. The data obtained can be the experimental proof for mildronate indication as saluretic medicine in the daytime under the conditions of salt and water retention in the organism.
Key words: mildronate, renal function, circadian biorhythms
