Sitdikova A.A., PhD, Associate Professor
Kazan (Volga Region) Federal University, Kazan

Dikopolskaya N.B., PhD, Associate Professor
Kazan (Volga Region) Federal University, Kazan

Bilalova G.A., PhD, Associate Professor
Kazan (Volga Region) Federal University, Kazan

Shaykhelislamova M.V., Dr. Biol., Professor
Kazan (Volga Region) Federal University, Kazan

Objective of the study was to study of the reaction of the sympathoadrenal system to local static load in children with features of autonomic regulation.
Methods and structure of the study. Children of 7 and 9 years of age of both sexes took part in the scientific work. The initial vegetative tone (IVT) was determined by the method of variation pulsometry using the automated cardiopulmonary complex REACARD, on the basis of which the children were divided into groups – sympathotonics, normotonics, vagotonics. Urgent adaptation of the sympathoadrenal system (SAS) to static load was studied by the shift in the excretion of catecholamines (CA) and DOPA in portioned urine, in response to a dynamometric test.
Results and conclusions. Dosed local static load in schoolchildren aged 7 and 9 years causes changes in the functional state of the SAS, the nature of which depends on the IVT, age and sex of the children. In boys aged 7 years - sympatho- and vagotonics, isometric efforts are accompanied by unfavorable shifts indicating the immaturity of the mechanisms of urgent adaptation of children of this age to static muscular activity. In boys aged 9 years, neurohumoral adaptive changes acquire a stable character, accompanied by positive, unidirectional shifts in the excretion of CA and DOPA in all the studied IVT groups. In contrast to girls, in whom at 7 years old the reactions of the SAS are more balanced, and at 9 years old they are accompanied by a decrease in reserve capabilities, which is most clearly expressed in the state of sympathicotonia.

Keywords: catecholamines, initial vegetative tone, local static load, schoolchildren aged 7, 9 years.

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