[The modification of a radiation lesion with 9a-homo-13-thiaprostanoids].

The radioprotective properties of 12 compounds of 9a-homo-13-thiaprostanoid series were investigated under gamma irradiation using the molecular model of beta-carotene radio-oxidation in oleic acid in vitro, erythrocyte radiomimetic model in ex vivo-in vitro system as well as in vivo radiation damage in mice. Most of these compounds stimulated the radio-oxidation of beta-carotene, however in this model two prostanoids with natural alpha-chain displayed radioprotective properties. Expressed membrane stabilizing effect of two 9a-homo-13-thiaprostanoid nor-analogues was revealed in radiomimetic model experiments.

[Proton magnetic resonance spectra of bound water in muscles].

The state of water in a muscle tissue was investigated using 1H-NMR. Water spectra in the muscle were found after holding it out at variable humidity and after the muscle species had been pressed with different effort. The NMR-spectra demonstrated the existence of two different water fractions with poor exchange between them.

[ATP synthesis by myosin during pH-jump].

It has been shown that a fast increase in pH of myosin solution leads to ATP formation de novo from ADP and Pi (about one ATP molecule per one myosin molecule). The obligatory condition for ATP synthesis was that the value of pH 7.9-8.

[Changes in NMR-relaxation of plasma protons in animals during experimental carcinogenesis].

Studies were carried out of changes of NMR-relaxation of water protons bound to blood plasma proteins of linear animals in the course of induced cancerogenesis and total reaction of the organism to damage. It has been shown that the ratio between the times of spin-lattice and spin-spin relaxation can serve as a criterion of the development of induced cancerogenesis at histologically determined stage of its development.

[Change in the metabolism of 7,12-dimethylbenz(a)anthracene under the influence of vitamin A].

The in vitro metabolism of 7,12-dimethylbenz(a)anthracene in its incubation with the liver microsomes, the liver and mammary gland homogenates of rats, kept on vitamin A-enriched diet, was studied. Vitamin A inhibited the formation of lipophilic metabolites and increased the generation of water-soluble metabolites. The amount of lipophilic metabolites extracted from the microsomes and the liver and mammary gland homogenates were decreased by a factor of 2.

[Circadian rhythms of ultraweak chemiluminescence of bean roots].

Circadian rhythms of ultra-weak chemoluminescence of bean roots were investigated. It was found that under periodical change of light and darkness and without subsequent illumination a periodical change of spontaneous chemoluminescence of bean roots was observed. (The study of antiradical activity of the substances extracted from the root showed the dependence of this activity on illumination conditions.

[Formalin-induced chemiluminescence in model protein-lipid systems].

Mechanisms of formalin--induced luminescence of protein-lipid complexes have been studied. Free radical reactions of lipid oxidation were shown to be necessary for generating luminescence quanta. The luminescence intensity was mostly promoted by fluorescing products formed in the reoxidized system protein-lipid.

[Metabolism of 7,12-dimethylbenz(alpha)anthracene in vivo].

The metabolism of 7,12-dimethylbenz(alpha) anthracene (DMBA) was studied, using labelled DMBA-H3, after intravenous injection of the carcinogen in female animals. The maximum excretion of the metabolites took place during the period ranging from 6 to 24 hours. The content of liposoluble metabolites in the urine was insignificant (about 6%), whereas in feces it was much higher (about 40%).