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N N Mushkambarov

Publications and source records attributed to N N Mushkambarov.

8 recordsLinked to original sources
PubMed1982

[Stability and viability of spermatogenic cells after their separation and fractionation].

Spermatogenic cells isolated from seminiferous tubules by enzymatic treatment are very sensitive to the action of Triton X-100. The cells isolated by mechanical dissociation of spermatogenic epithelium are destroyed during storage. On the contrary, the cell separation by sedimentation velocity technique in human serum protein gradient leads to cell stabilization. As the result, the cells in collected fractions kept their living capacity and, what is more, their specific features.

Animals↗
PubMed1982

[Proteins of mouse spermatogenic cells. I. Enzymatic activity and electrophoretic spectrum].

The proteins characteristic of the whole period of differentiation constitute the main bulk of soluble proteins in the spermatogenic cells. Their content and enzymatic activity are subject to marked changes during spermatogenesis. The activity of glycolysis and pentose cycle enzymes is jointly changed; the fluctuations of enzymes of pyruvate oxidation and Krebs-cycle are in antiphase. Sorbitol dehydrogenase suffers marked activation in the late spermiogenesis. This process is facultative and is not expressed in the cells of young animals. It is suggested that the level of sorbitol dehydrogenase may serve as an index of biochemical maturity of late spermatids.

Animals↗
PubMed1978

[Properties of DNA-methylase reaction in isolated nuclei of normal and regenerating rat liver].

Evidence from comparative determination of DNA radioactivity methylation degree of acidic extraction and chlorophormic deproteination of the samples suggest that the former technique is a more efficient one. The properties of the DNA-methylase reaction in isolated rat liver nuclei were studied. The DNA-methylase activity is found to be considerably stable during incubation of the nuclei at 37 degrees C; a broad pH-optimum in the alkaline region is observed (pH 8.6--9.8); this activity is inhibited by Mn2+, nucleotides, actynomycin and S-adenosyl methionine analogs and is activated by Mg2+; the incorporation of methyl groups into DNA is reversible. The data suggest that the DNA-methylase activities of the nuclei isolated at different stages of regeneration do not show substantial variations. No differences in DNA methylation before and after DNA synthesis in the regenerating nuclei were observed. Inhibition of DNA synthesis in the course of regeneration does not decrease the level of DNA methylation. The interrelationship between methylation and replication of DNA is discussed.

Animals↗
PubMedDate not supplied

[Proteins of mouse spermatogenic cells. II. Age differences at individual stages of differentiation].

The spermatogenic cells of the adult and young mice differ by the content of certain electrophoretic fractions of proteins and the activity of a number of enzymes (glucose-6-phosphate, sorbitol and pyruvate dehydrogenases). The expression of age differences changes in the process of differentiation. It is suggested that the differences found are of dual nature: they are due to both the "immaturity" of young animals and the age processes per se in adults; the role of the latter decreases as the differentiation proceeds.

Aging↗