ABSTRACT
Background: Under physiological conditions, the activity of the formation of active oxygen is low. The activity of these processes is intensified under stress-induced situations. This study aimed to investigate the role of free-radical oxidation (FRO) in adrenal tissues and immunocompetent organs and cells in mature white rats after 6 hours of immobilization stress. Methods: The studies were performed on 40 White male rats of the Wistar line with a bodyweight of 200 to 240 g. Two series of experiments were conducted: I series: determination of indices in intact rats (10 rats); II series: determination of indices after a 6-hour immobilization stress action on them. Animals of II series were divided into 3 groups of 10 rats in each: group 1: those undergoing acute immobilization stress, withdrawal from the experiment in 1 hour; group 2: those undergoing acute immobilization stress, withdrawal from the experiment in 25 hours; and group 3: those undergoing acute immobilization stress, withdrawal from the experiment in 49 hours. The obtained data were processed by statistical methods with the help of the "Biostat" and "Excel" software packages. Results: In groups 1, 2, and 3, the animals were simulated acute immobilization stress by fixing the animals for 6 hours in bright light. The results of the conducted studies indicate changes in lipid peroxidation and antioxidant system (LPO-AOS) in case of immobilization stress-excitation. In developing free-radical pathology at immobilization stress-excitation, the more expressed disturbance of LPO-AOS, and accordingly the intensity of lipoperoxidation in the structural membrane of all investigated organs was high at the initial stage of exposure. Conclusion: At 49 hours after immobilization, stress less pronounced influence on the lipoperoxidation process was noted. The increase in the intensity of excessive lipoperoxidation testifies to the inhibited manifestation of AOS in the organism.
ABSTRACT
BACKGROUND: We studied the life history of Gagea graeca (L.) A. Terracc. (sect. Anthericoides) by field surveys on the Greek island of Crete, including quantitative analyses of 405 individuals, estimation of resource allocation by measuring the nitrogen content of different plant organs, assessing seed set and recording genetic diversity via amplified fragment length polymorphism (AFLP) analyses. In contrast to most species of the genus G. graeca seems to be a short-lived perennial, developing several characters that are rather typical for annual plants. RESULTS: Although seed set varies largely, flowering plants produce many (68 ± 79) small, flattened seeds (mean weight 73 ± 22 µg) in comparison to a single bulbil. If measured as nitrogen content of the respective plant parts, investment in seeds (25%) is much higher than that in bulbils (4%). In addition, the threshold for flower formation (expressed as bulb size where 50% of the plants form the respective structure) is with 2.17 ± 0.05 mm lower than that for bulbils with 2.80 ± 0.16 mm. This is in accordance with AFLP analyses revealing predominantly sexual reproduction (only 9.1% of 110 investigated plants belonged to clones). CONCLUSION: In the genus Gagea early, predominantly sexual reproduction seems to be characteristic for species from arid habitats, coupled with a low proportion of clonal plants.
