The role of lysosomal proteinases and estradiol in neurodegeneration induced by beta-amyloid.

Activation of lysosomal degradation process in nervous tissue may be neuroprotective. One of the factors that may influence on expression of lysosomal proteinases is the sex hormone, estradiol (E2). In this regard the expression of lysosomal proteinases after intracerebral injection of beta-amyloid peptide (Aβ) was investigated as well as the neuroprotective effect of E2 in Aβ-induced neurodegeneration.

[Calpain system dysregulation in rat brain at beta-amyloid-induced neurodegeneration].

Experimental evidences of calcium-dependent proteolysis dysregulation in brain of murine model of Alzheimer disease were obtained. Experimental treatment consisted in intra-hippocampal injection of amyloid beta-peptide (AP1-40) promoted activation of main calpain forms in murine brain along with decrease incontent of natural calpain inhibitor, calpastatin. As a result of prognostic experiment on the correction of neurodegeneration induced in murine the neuroprotective properties of steroid hormone estradiol were confirmed and one of the possible protective action mechanisms was suggested.

[Mechanisms of reproductive behavior in humans: olfactory markers of males' attractiveness].

The present work represents a pilot study in the area of olfactory communication in humans. On the basis of experiments, it is demonstrated that women are able to detect, by means of smell, a number of morphological and psychological characteristics of men. The samples of sweat from 29 young men were collected, as well as anthropometry measurements (interpupillary distance, height and width of the lower jaw, and so forth) and behavioral characteristics (personality questionnaire NEO, risk-taking questionnaire, Sandra Bem masculinity and femininity indices, a self-rating on aggression Buss-Perry questionnaire).

[Level of neuroactive steroids in the brain, and gender-related differences in formation and decrease of conditioned reflex in rats].

We investigated gender-related differences in dynamics of the brain sexual steroids during learning and the decrease of conditioned reflex in the modeling experiment. It was revealed that, before training to conditioned reflexes, females manifested a greater anxiety than males. Significant differences between males and females in formation of the conditioned reflex of passive avoidance were not revealed, whereas the conditioned response decrease were by 2-3 days faster in male rats than in females.

[Sex-related peculiarities of conditioned reflex activity and dynamics of sex steroids in the brain].

Sexual peculiarities of dynamics of brain sex steroids in the process of learning and extinction of the conditioned reflex of passive avoidance have been studied in model experiment. Prior to learning of conditioned reflex, females were found to be distinguished by manifestation of anxiety and fear as compared with males. At formation of the conditioned reflex, no significant sex differences were detected between males and females, whereas extinction of the conditioned reaction of passive avoidance in rat males occurred by 2-3 days faster than in females.