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The effects of dynamic and static load on the intracellular concentrations of sodium [Formula: see text] and potassium (K+i) in m. soleus and m. biceps, respectively, were studied in mice. Both dynamic (swimming for 60 min) and static (hanging on the grid for 40 min) load led to a 2-fold increase in [Formula: see text] level, a decrease in K+i concentration by 25-35%, and 3-4-fold increase in the [Formula: see text] ratio. These effects of dynamic and static loads on the studied parameters remained unchanged in mice subjected to regular physical exercise (swimming or hanging on the grid for 1 h a day over 4 weeks). Our results suggest that dissipation of sodium and potassium transmembrane gradients during physical exercise can be considered as a factor of regulation of functional activity of skeletal muscles, which includes changes in transcription and translation of myokines observed previously.

The effect of forced treadmill running on the level of some cytokines in skeletal muscles of mice with a model of type II diabetes mellitus was studied. The mouse model was developed using a 12-week high-fat diet; physical loading in the form of forced treadmill running was applied for 4 weeks. The concentration of myokines in m. gastrocnemius was determined by an enzyme-linked immunosorbent assay (ELISA). Diabetes formation in mice was accompanied by changes in the skeletal muscle concentration of two pro-inflammatory cytokines: an increase in IL-6 and a decrease in IL-15. Forced treadmill running loads had differential effects on the level of myokines in healthy and sick mice. In healthy animals, there was a decrease in IL-6 and IL-15 concentrations and an increase in the leukemia inhibitory factor (LIF) concentration in skeletal muscles after 4 weeks of regular forced running. At the same time, in diabetic mice, IL-6 and IL-15 concentrations increased, while the LIF concentration decreased after forced running loads. The NAP3 concentration in skeletal muscles was found to be insensitive to both the development of type II diabetes mellitus and regular forced treadmill running.

The influence of dynamic and static load on the plasma level of myokines in strength-and endurance-trained athletes and untrained subjects has been studied. The range of myokines has been found to depend on the type of loads and the level of fitness. Dynamic and static exercises have different effects on the level of myokines in athletes and untrained subjects. The dynamic load increases the level of IL-6 and IL-8 in the plasma of athletes, while the static load increases the concentration of IL-15 and LIF. At the same time, no increase in the level of IL-8 after cyclic loading or in IL-15 after a static load has been observed in the control group. These differences may be based on a number of mechanisms. The cellular composition of skeletal muscles and the phenotypic features of muscle fibers, changing as a result of regular exercise, can modify the processes of myokine production. However, the processes of transcription in muscle fibers are much more important; the most important ones are HIF-1α, [Ca2+]i and [Na+]i/[K+]i-dependent intracellular signaling pathways. The modification of these mechanisms caused by different physical loads and intensity is of great interest since it is a promising way to influence the metabolic processes at the cellular and systemic levels, which is very helpful in both improving athletic performance and correcting metabolic disorders in a number of socially significant diseases.

In the present study was to investigate the effect epithelium on the tone smooth muscle of the airways of guinea pigs under physiological conditions and when forming of experimental asthma. It was found that the amplitude of contractile responses decreased by histaminergic, and serotonergic effects in the presence of epithelium in the control group. Influence epithelium dilatation adrenergic reactions depended on the type of pretreatment factors. The amplitude of the relaxation was reduced in the case of pre-treatment with a solution of potassium, the amount of dilation increased by pretreatment with histamine. The impact of epithelium on contractile responses of smooth muscles disappeared when forming of hyperreactivity.

Skeletal muscle cells secrete a variety of hormones and cytokines, which are referred to as myokines. Different modes of exercise are the main factor of myokines producing. The myokines expression level is increased in an exponential fashon proportional to the length of exercise and the amount of muscle mass engaged in the exercise. These myokines are described to communicate with cells in an autocrine/ paracrine manner. Thus it ensures the maintenance of homeostasis and adaptarion to physical stress. This myokines role is provided by a vriety of effects. It is assumed that exercise increases myokines transcription via signaling systems that are activated in response to a decrease in the partial pressure of oxygen, increasing the concentration of [Ca²⁺] i and AMP. Significant prospects have the myokines investigation of the role in the different disorders correction. So now accumulated enough data for myokines consideration as a single functional system, which plays an important role in the adaptation mechanisms to the habitual exrcise.