Ultrastructure of Myofascial Trigger Points of Skeletal Muscles of Rats after Photobiostimulation with Low-Intensity Red Light.

The effectiveness of low-intensity red light on myofascial trigger points in skeletal muscle of mature rats was evaluated by electron microscopy and high-resolution respirometry. The revealed changes in mitochondrial ultrastructure and activity of the respiratory chain enzymes indicate the development of hypoxia in the simulation area. Under the influence of low-intensity red light on myofascial trigger points, a decrease in the number of destructively altered muscle fibers and stimulation of mitochondrial respiration were found. These findings indicate intracellular regeneration and the stimulating effect of low-intensity red light on plastic processes.

[Age-related aspects of male rats sexual behavior with different senescence rates].

Social and sexual behavior of males Wistar and senescence-accelerated OXYS rats was studied. The experimental model excluding direct interaction between partners showed that the exploratory activity decreased with aging in rats of both strains, but social motivation didn't change. No interstrain differences in intensity of sexual motivation in the presence of an inaccessible receptive female were observed in 4-month rats. The level of sexual motivation of 12-month Wistar rats didn't differ from that of 4-month animals. However, in 12-month OXYS males, sexual motivation was decreased as compared to both 4- and 12-month Wistar rats. The same regularities were found under conditions of direct interaction with a partner. Behavioral changes in 12-month OXYS rats were considered as genetically determinate abnormality at the initial stage of sexual behavior, i.e., sexual motivation. The results suggest the accelerated senescence of the reproductive system of OXYS rats.

[Yeast resistance to polyene antibiotics. I. Production of Saccharomyces cerevisiae mutants resistant to nystatin and their genetic analysis]. / Rezistentnost' drozhzhei k polienovym antibiotikam. Soobshchenie I. Poluchenie mutantov Saccharomyces cerevisiae, rezistentnykh k nistatinu, i ikh geneticheskii analiz.

239 nistatin-resistant mutants were selected after UV-irradiation of yeasts. Phenotypical analysis has revealed two main groups of the mutants: 1) resistant to nistatin and resistant or sensitive (in different combinations) to haptaens; 2) resistant to nistatin and having an increased resistance to haptens. It is found that the sensitivity dominates over the resistance and hyper-resistance. Genetic analysis of the mutant collection has shown that the resistance to nistatin is determined by 5 nuclear genes (hysr). Hyper-resistance is controlled by mutations in other genes, which are not connected with stable phenotype. Genes of hyper-resistance can be considered as minus-modificators of pleiothrophic cross-resistance, characteristic of hysr genes. Plus-modificator genes of polyenic resistance are described. The gene hysr1 is linked with its chromosome.

[Supersensitivity to levorin and amphotericin B in several Saccharomyces cerevisiae mutants resistant to nystatin]. / Superchuvstvitel'nost' k levorinu i amfoteritsinu v nekotorykh mutantov Saccharomyces cerevisiae, rezistentnykh k nistatinu.

104 mutants resistant to nystatin were isolated after UV-treatment of two haploid marked strains of Saccharomyces cerevisiae. The analysis of resistance to three polyene antibiotics allowed to determine 8 phenotype classes of mutants including those resistant to nystatin but in various combinations showing hypersensitivity to levorin and (or) amphotericin B. The analysis of UV absorption spectra of sterolic extracts prepared from cells of different mutants showed that similar quality changes in sterol composition could be associated both with polyresistant an supersensitive phenotype. New type of mutants resistant to nystatin and supersensitive to levorin and (or) amphotericin B seems to be promising for studies on the mechanisms of action of polyene antibiotics, the bases of resistance to them and also in consideration of the possibility to increase the efficiency of antimycotic antibiotic therapy.

[Change of current-voltage characteristics of amphotericin B ion channels accompanying its incorporation into the membrane]. / Izmenenie bol't-ampernoi kharakteristiki ionnykh kanalov amfoteritsina B pri ego vstraivanii v membranu.

Non-linearity of amphotericin B current-voltage characteristics is determined by means of the third harmonic generated in the membrane. A change of the sign of non-linearity is revealed during incorporation of antibiotic molecules into a membrane, i. e. the incorporation is not a simple increase of the number of similar ionic channels in the membrane.

[Nitrogen metabolism of Streptomyces antibioticus on media with various glucose contents]. / Azotnyi metabolizm Streptomyces antibioticus na sredakh s raznym soderzhaniem gliukozy.

The dynamics of the glutamine synthetase and glutamate dehydrogenase activity was studied during cultivation of Str. antibioticus on media with different contents of glucose and ammonium sulfate. No correlation between the enzymes activity and the levels of oleandomycin production by the mycelium was observed. It was shown that the levels of oleandomycin biosynthesis repression by glucose did not depend on ammonium sulfate concentration in the medium.

[The influence of sexual experience on sexual motivation and copulatory behavior in male rats].

The influence of sexual experience on male behavior induced by a possible sexual or social partner was studied in 12-month-old Wistar rats in direct interaction or under conditions excluding their direct partner contact. Sexually experienced males demonstrated an interest towards a social partner situated behind the partition to a greater extent than sexually naive males, whereas in direct contact sexually naive males showed greater communicative behavior than experienced ones. All the males demonstrated greatest activity in the presence of a receptive female. Sexual experience did not influence the motivational component of male sexual arousal: the intensity of sexual motivation in the presence of a receptive female did not differ in experienced and naive males. However, sexual experience significantly changed the character of consummatory pattern of sexual behavior increasing its expression. The frequency of such copulatory parameters as mounts and intromissions amount was increased while latency time was decreased.

[Age-related aspects of male reproductive function in rats with normal and accelerated senescence].

The study was performed on male rats with normal rate of aging (Wistar) and senescence-accelerated OXYS rats. Sexual motivation behaviour, activation of endocrine testicle function under condition of sexual activation, gravimetric rates were studied in male rats of different age. Potential ability to spermatogenesis in testis was studied in 14-month male rats. Males underwent the partition test: a receptive female was introduced into the male's cage, but the male and female were separated by a transparent partition. The number of approaches to the partition and total time spent near partition during the test served as an index of sexual motivation. Activation of hypothalamic-pituitary-testicular complex was estimated by plasma testosterone level. A decrease of sexual motivation in the 14-month OXYS males was observed in comparison both with 3- and 6-month OXYS rats and with 14-month Wistar rats. However, no decrease in hormonal component of sexual arousal in aged OXYS males rats was detected. No interstrain differences in potential ability to spermatogenesis in 14-month rats were observed. However, no interstrain differences in the weights of androgen-dependent reproductive organs (testes and preputial glands) were observed under 18-month age. However, the weight of epididymisis in 24-month OXYS rats was significantly smaller than in Wistar rats.