Pichurina N. The power of a skeletal muscle contraction of white rats by difference thyroid status

In experiments "in situ" are lawn influence of various models experimental hyperthyroidism in character (from easy degree of expressiveness to the heavy form of thyreotoxicosis) on the main parameters of power of isometric contraction of a skeletal muscle of white rats are revealed at development of exhaustion and adrenergic stimulations. For the first time, it is shown, that the muscle of white rats gets high functional abilities in conditions "in situ" at experimental hyperthyroidism easy degree of expressiveness. Mobile and power indicators of reduction as a result improve, the latent period of contraction is shortened, time of development of the maximum pressure is reduced, isometric pressure increases and speed of its development increases. For the first time, it is established, that a temperature cost of muscle contraction the certificate accrues together with deepening of degree by expressiveness experimental hyperthyroidism - from easy degree to the average and heavy form of thyreotoxicosis in conditions "in situ". For the first time, it is shown, that at the development of exhaustion the temperature cost by muscular contraction at white rats always increased "in situ" in conditions irrespective of thyroid status and type of isometric contraction. For the first time it is revealed adrenostimulating effect of isopropilnoradrenaline on parameters of power of muscular contraction. This effect is shown only at animals of euthyroid group and at rats with easy degree experimental hyperthyroidism. It is supposed, that the mechanism action of triiodthyronine on a skeletal muscle is the effect of a hormone on increase of power inputs on unit of isometric force, and also ability to have modulating an effect on the majority effects of catecholamines. Position about modulating action of various doses of triiodthyronine on the functional characteristic of a skeletal muscle in conditions in situ is proved, including at exhaustion and stimulation of catecholamines.