[Experience in analyzing the functional structure of thermogenesis based on pharmacologic testing]. / Opyt analiza funktsional'noi struktury termogeneza na osnove farmakologichskogo testirovaniia.

In white rats both adapted and unadapted to cold and in lemmings the total heat production and skeletal muscles contractile activity under noradrenaline and propranolol were estimated at different ambient temperatures. In rats, the regulatory and adaptive changes of heat production occur due to a significant extension of adrenergically modulated part of contractile thermal effect in muscles, as well as to increased nonshivering thermogenesis. In lemmings, the adaptability to cold is maintained chiefly by nonshivering thermogenesis and leads to no alterations in muscle energetics.

[Influence of adaptation of hypoxia on the relationship between tissue respiration, temperature and oxygen tension in vitro]. / Vliianie adaptatsii k gipoksii nazavisimost' tkanevogo dykhaniia ot temperatury i napriazheniia kisloroda in vitro.

The effect of adaptation to hypoxia on rat tissue respiration at different pO2 and temperature in vitro was studied. The temperature coefficient Q10 and the Michaelis constant Km for oxygen were estimated. The tissue sensitivity to low pO2 and low temperature obviously decreased while the tissue affinity for oxygen and the direct temperature dependence on Km increased in animals adapted to hypoxia. A functional interrelationship between adaptational changes of Q10 and Km of tissue respiration in different organs was revealed. The data obtained suggest participation of cellular oxidation changes in adaptive increase of oxygen affinity.

[Functional topography of somatic muscles in euciscus idus]. / K funktsional'noi topografii somaticheskoi muskulatury iazia Leuciscus idus

The intensity of tissue respiration and anaerobic glycolysis, as well as the activity of succinic oxidase, cytochrome oxidase, lactate dehydrogenase and ATPase in skeletal muscles of the ide L. idus significantly increase from head to tail. Cranio-caudal gradients of the intensity of tissue respiration and the enzymic activity are especially evident in the red muscle, namely m. lateralis superficialis. In white m. lateralis magnus, the gradient of glycolytic activity is most pronounced. Biochemical and morphological peculiarities of muscles are discussed in relation to functional profile of the latter.