Search

These studies were dealing with muscle protein depletion in rats under the heart hypertrophy induced by aorta coarctation or under liver regeneration after partial hepatectomy. The last experimental model was also used in order to establish how far such protein mobilization from muscles is realized during their simultaneous adaptation to local overload or disuse induced by a surgical method. 3 and 7 days after induction of hypertrophy of organs investigated, the quantities of sarcoplasmic, myofibrillar and stroma proteins were measured in last-twitch (m. extensor digitorum longus, m. biceps brachii) and slow-twitch (m. soleus) muscles. The contributions of protein biosynthesis and/or protein degradation change into muscle protein loss were evaluated by specially elaborated radiotracer method. The data obtained demonstrate that the pattern of muscle protein mobilization depends on nature of organ and rate of its hypertrophy. The process occurs differently in muscle of different type and in various muscle structures. It appears to be potentiated in overloaded muscles and to a lesser extent in unused ones. The loss of muscle proteins is certainly associated with inhibition of their biosynthesis. Increased degradation (or release) of preformed (non-labelled) protein molecules may also contribute to this loss whereas degradation of newly-formed (labelled) molecules does not change appreciably, possibly because their distribution in muscle structures is non-uniform.

A universal scheme for the treatment of water containing different concentrations of organic compounds is described. The treatment is based on the principle of the water saturation with an active oxidant followed by aerobic purification in units with microflora fixed on active carbon. Active chlorine forming during the electrochemical treatment provides the water disinfection and plays the role of a source of the formation of monatomic and molecular oxygen during the dechlorination.

A technological process is described for the submerged biological treatment of household and industrial sewage and in particular pharmaceutical industry and pooled sewage. The submerged biological treatment of the sewage to the maximum permissible concentrations adopted for the water in fish farming is achieved by the use of submerged and immobilized microorganisms in a multistage process under anaerobic and aerobic conditions and the use of chemically active and inert materials as carriers of the microorganisms inducing certain biological processes. The data on the ecological estimation of the treated sewage by the stages of the technological process are presented.

The distribution in the organism of radioactivity after intratracheal administration of labelled heparin and its quarterly ammonium salt oligomer-25 conidine was studied. Within 25 hours the preservation of a high level of radioactivity in plasma, its decrease in other investigated organs and the accumulation in mast cells of the peritoneal cavity were observed. The involvement of the lymphatic system in heparin metabolism was shown. A positively charged oligomer conidine administered intratracheally, in contrast to heparin, was not detected in blood plasma in the studied time. The accumulation of the drug in the lung tissue, lymph nodes and excretory organs was noted.

Protein synthesis in the heart, lungs, liver, pancreas, thymus, kidneys, skeletal muscles and testes of the 22-day Cosmos-605 flight and synchronous rats was studied with the aif of 14C-amino acid incorporation. On the 2nd postflight day both flight and synchronous rats showed an increased synthesis of heart sarcoplasmatic proteins. On the 26th postflight day the rate of incorporation was normal. On the 2nd and 26th days the synthesis of myofibrillar proteins in the m. quadriceps femoris was inhibited in flight animals postflight day the rate of incorporation was normal. On the 2nd and 26th days the syn-only. On the 2nd and 26th days the liver of the flight and synchronous rats showed qualitatively similar changes in protein metabolism of subcellular structures. No changes in the protein synthesis of other organs tested were detected.

With the aid of C14-leucine incorporation into proteins the protein synthesis in the red (m. soleus) and white (m. extensor dig. longus) skeletal muscles of flight and synchronous rats from the Cosmos-605 experiment was investigated. On the 2nd postflight day the total synthesis of proteins (as calculated per whole muscle) in the red muscle of flight rats remained unaltered. Therefore, distinct atrophy of this muscle that was seen only in flight rats can be attributed to increased degradation of proteins. On the 2nd postflight day the white muscle of both flight and synchronous rats showed moderate atrophy, not only increased protein degradation but also inhibited protein synthesis contributes to this.

Using a radioindicator method the authors studied the effects of hydrocortisone on the synthesis and breakdown of sarcoplasmic and myofibrillar proteins in white (m. extensor digitorum longus) and red (m. soleus) functioning and idle skeletal muscles of rats. It was found that in addition to the catabolic effects, i.e. inhibition of the protein synthesis and/or stimulation of their breakdown the hormone also exhibited an "anticatabolic" effect that manifested itself in an inhibition of the protein breakdown. This effect was observed in all the cases (except the white functioning muscle) simultaneously with the protein synthesis inhibition, thus counteracting to this or that degree the development of atrophic reactions in the muscles.

Protein biosynthesis is studied in red and white rat shank muscles in vitro. It is found that the incorporation rate of 14C-lysine in red muscle was 2-fold higher than that in white muscle. The difference in the lysine incorporation rate into muscle proteins studied increased with the increase of lysine molar concentration in the incubation medium, which was probably due to a selective protein synthesis activation in the red muscle. A higher level of 14C-lysine incorporation in red muscle proteins was found under similar uptake of the labelled amino acid in both red and white muscles. RNA synthesis rate was the same in both muscles and its inhibition with actinomycin D did not affect the ratio of protein synthesis rates in red and white muscles.

Radiotracer studies in vivo on protein biosynthesis have been made in red (m. soleus) and white (m. extensor digitorum longus) rat shin muscles during their disuse atrophy caused by foot exarticulation. The rate of protein biosynthesis (as calculated per mass unit of total RNA) was increased in the white muscle on the 4th and 14th days, being unaltered on the 7th day after the surgery, but this rate was decreased in the red muscle at all these stages. The data obtained suggest that all these stages. The data obtained suggest that the atrophy, more pronounced in the red muscle than in the white one, can be mainly attributed in the former to decreased protein biosynthesis but in the latter to the increased protein degradation.

Using a radioindicator method, the metabolism of sarcoplasmic and myofibrillar proteins was studied in vivo at different stages of hypokinesia in rats. It was shown that the true muscle atrophy and the lowered content of both protein fractions during the first two weeks are due to sharp inhibition of sarcoplasmic protein biosynthesis as well as to deceleration of biosynthesis and acceleration of degradation of actomyosin. In hypokinesia the muscle mass does not increase within 3-8 weeks largely due to the acceleration of degradation of the de novo synthesized components of contractile proteins. In early hypokinesia a stressory mechanism plays an essential role in the pathogenesis of protein metabolism disturbances.