COMPARATIVE CHARACTERISTICS OF THE TERMINAL LINK OF GLYCOLYSIS IN THE MUSCLES OF ADULT ANIMALS AND THEIR OFFSPRING

The organism of sexually mature individuals differs significantly from the organism of immature individuals in a number of anatomical, physiological and biochemical parameters. The aim of the work was to investigate the state of the terminal link of glycolysis in the muscles of sexually mature animals and their offspring. The isoenzyme spectrum of LDH in the myocardium of sexually mature animals is characterized by a high content of LDH1 and LDH2 isozymes rapidly migrating to the anode. The isoenzyme spectrum of LDH in skeletal muscles of mature animals is represented mainly by the LDH 5.A feature of the isozyme spectrum of LDH in the tissues of rat pups is that the content of LDH1 and LDH2 is significantly reduced in the myocardium. Their number is 1.2 and 1.13 times, respectively, less than in sexually mature animals. Against this background, the content of LDH3 increases slightly, the content of LDH4 exceeds twice, and that of LDH5 is more than 6 times the indicators of sexually mature animals. In skeletal muscles of rat pups, the dominant content of LDH5 and LDH4 increases and this occurs due to a decrease in the activity of LDH3 (more than 1.5 times), LDH2 (more than 2.3 times) and LDH1 (2.2 times) compared with sexually mature animals. The data obtained indicate that in the myocardium and skeletal muscles of rat pups there is a greater percentage of isoenzymes formed from M-subunits functioning under anaerobic conditions, and with age, as a result of epigenetic transformations, the content of H-subunits increases.

THE ACTIVITY AND ISOFORMS OF SUPEROXIDE DISMUTASE IN TISUES OF REPRODUCTIVE ORGANS OF RATS

The aсtivity of superoxide dismutase, the content of its isoforms in testis, epididimis, and in epididimal spermatozoa of pubescent rat males were studied. The experiments were performed on adult male rats (age 5 - 6 months). After decapitation, the testes and the epididimis were taken, from which the spermatozoa were washed with 0.9 % sodium chloride solution. The total protein and activity of superoxide dismutase (SOD) were determined in the supernatant and the sperm suspension. SOD isoforms were detected after electrophoresis in 10 % polyacrylamide gel by specific staining of gel plates with nitrosine tetrazolium. The highest activity was found to be in the tissue of the testes (18.2 ± 2.59 IU/mg of protein), less on 34.6% in the epididymis and the lowest on 46.7% in epididymal sperm. Electrophoresis in 10 % polyacrylamide gel and specific staining in the tissues of testis, epididymis, and epididymal sperm of rats revealed five major SOD isoforms, which, depending on the speed of movement in PAAG, were labeled, from maximum to least mobile, such as S1, S2, S3, S4 and S5. The specifity of testicular tissue is the presence of two minor isoforms (S1a- and S1b-isoforms), which are characterized by high electrophoretic mobility and lower intensity of manifestation, and the color disappears over time, unlike other proteins of the enzyme. It was found that the SOD isoenzyme spectrum is characterized by tissue specificity and depended on the physiological and functional features of the tissue of the reproductive organs of males and spermatozoa. In the testis tissue, S2 isoform was in the largest amount– 36.7 ± 1.91%, less and almost the same content of S1-, S3- and S4-isoforms (18.0 ± 3.27, 19.3 ± 3.98 and 15.7 ± 2.15%) and the least – S5-, S1a- and S1b-isoform (6.2 ± 1.20%; 2.2 ± 0.03 and 1.9 ± 0.01%). In the epididimis tissue, the content of the S3-isoform was higher on 17.9% and S2- and S1- respectively on 7.9% and 4.9%, respectively, compared to the testis. SOD isoenzymes of epididymal spermatozoa are characterized by a high content of S2 isoforms, which is more on 11.2% than in the testis, and the content of S1 isoforms, by contrast, is lower on 10.0%. The established differences in the content and activity of individual isoforms of the enzyme indicate the existence of tissue specificity of SOD proteins, due to the functional characteristics of the studied tissues. Optimal protection of sperm from O2• - in the process of their differentiation and maturation is ensured by the activity of different SOD isoforms, confirming the established differences in the isoenzyme spectrum.

Isoenzymes spectrum of genes expression of cattle in different directions of productivity

While studying the peculiarities of the species of genetic structure of cattle, depending on the direction of productivity, one can predict, that there may be certain mechanisms that have an intermediate role between the genetically determined polymorphism of biochemical markers and the variability of complexity of the signs of productivity. One of such mechanism may be the variability of the “biochemical phenotype” of different organs – a number of organ-specific isoenzymetric spectra of genetic-biochemical systems. In this regard, in this experiment organ-specific peculiarities of the isoenzyme spectrum of various enzymes in animals of dairy and meat production were considered. For this experiment, samples of meat, and then dairy animals in pairs were placed in the electrophoretic block in the following order: lungs, heart muscle, spleen, skeletal muscle and liver. The features of the organ-specific isoenzyme spectrum of the enzymes of the general intracellular metabolism are breed and species specific. Therefore, a comparative analysis of the organ-specific spectrum of isoenzymes of various genetic-biochemical systems in these studies was performed on a small number of animals (3–5 heads). The features of the isoenzyme spectrum were evaluated by genetically-determined polymorphisms of groups of genetic-biochemical systems. Experiments were carried out on samples of homogenates of organs obtained with the addition of trilon-B. Polymorphism of enzymes was evaluated using a method of electrophoretic protein separation in 13% starch gel in horizontal chambers with subsequent histochemical staining. These searches indicate the presence of pronounced organospecificity of the isoenzyme spectrum of purinucleoside phosphorylase, malate dehydrogenase, malic enzyme, and lactate dehydrogenase in cattle. The intraspecific differences of the organ-specific isoenzyme spectrum were revealed. It has been shown that the expression of the genetic and biochemical systems under investigation is significantly different in cattle of dairy and meat production lines in the cardiac and skeletal muscles. The “biochemical phenotype” of the heart muscle and skeletal muscle of dairy cattle is significantly different from the livestock of the meat production direction. Such studies may lead to the identification of characteristic genotypes in a complex of genetic-biochemical systems, which are closely related to the corresponding complex of economic benefits.

Growth and development of testes in domesticated and hybrid (wild x domesticated) yak bulls

Testicular tissue was studied in domesticated yak and in wild yak x domesticated yak (F1 and F2) bulls at 6, 12, 18 and 24 months of age by stereology for quantitative histology and by comparative studies on the lactate dehydrogenase (LDH) isoenzyme spectrum, LDH activity and the percentage content of LDH isoenzymes in testes. The results indicated that all three types of yak were similar in both the characteristics of ultrastructure of testicular tissue and the degree of germ cell development. The process of spermatоgenesis was initiated and sperm were produced for the first time at the age of 12 months in all three yak types. All yak types exhibited similar age-related increases in weight of testes, volume density of both the seminiferous tubules and seminiferous epithelium and height of seminiferous epithelium but all these indexes were slightly affected by season. The number of LDH isoenzyme bands after electrophoresis varied with age as follows: four bands were present at 6 months of age, five bands at 12 and 18 months and six bands at 24 months of age. The sixth band was LDH-x, which appeared between the LDH4 and LDH5 band. These results indicated that yak bulls reach sexual maturity at 24 months of age and that puberty is not affected by infusion of wild strains.