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Morphological, morphometric, and ultrastructural analysis of the nerve fibers in the colon mucosa was performed in C57BL/6 mice at various terms of development of acute colitis induced by dextran sodium sulphate. The nerve fibers were labeled with antibodies to pan-neuronal marker βIII-tubulin. The progression of inflammatory and ulcerative processes in the mucosa on days 3-5 was associated with hyperplasia and hypertrophy of nerve fibers that peaked on day 7 after colitis induction. Ultrastructural analysis at all terms of colitis development showed moderate degeneration of axons. Thus, hypertrophy and hyperplasia of the nervous fibers in colon mucosa in experimental acute colitis correlated with aggravation of the ulcerative process in the mucosa. These changes are determined by alteration of histoarchitectonics and regenerative processes in the mucosa.

Morphological manifestations of acute colitis and subpopulation composition of colon lymphocytes were studied in male and female C57Bl/6 mice with acute dextran-induced colitis. We evaluated the severity of colitis symptoms, morphological changes in the colon, and prevalence of epithelialized and non-epithelialized ulcers. The subpopulation composition of lymphocytes (CD3-CD19+ B cells, CD3+CD4+ T helpers, CD3+CD8+ cytotoxic T cells, and CD4+CD25+FOXP3+ regulatory T cells) was assessed by flow cytofluorometry in suspension of colon cells prepared by enzymatic disintegration. In males, clinical manifestations of acute colitis and morphological changes were more severe and the prevalence of non-epithelialized ulcers was higher than in females. In females, the content of T, B, and regulatory T cells in the colon wall was higher, while the content of cytotoxic T cells was lower than in males. In females with acute colitis, the absolute lymphocyte count and the content of B cells and regulatory T cells decreased, while the percentage of cytotoxic T cells increased in comparison with intact animals. In males with acute colitis, the levels of regulatory T and B cells increased in comparison with the corresponding parameter in intact animals. Morphological changes and changes in the lymphocyte subpopulations, detected in males and females with acute colitis, were determined by different levels of sex steroid hormones.

Morphological changes in the mesenteric lymph nodes of male C57Bl/6 mice and subpopulation composition of lymphocytes in these nodes were studied in experimental acute and chronic ulcerative colitis induced by sodium dextran sulfate. Acute and chronic ulcerative colitis was associated with the development of reactive changes in the mesenteric lymph nodes. These changes were of mixed type and were characterized by follicular hyperplasia and sinus reaction. The content of CD19(+) B cells in the mesenteric lymph nodes decreased in acute ulcerative colitis, while the content of CD3(+)CD8(+) cytotoxic T cells increased, which presumably reflected activation of Th1 reactions. The increase in the count of CD4(+)CD25(+)FOXP3(+) regulatory T cells and CD3(+)CD8(+) cytotoxic T cells was due to intensive migration of lymphocytes from the thymus and the colonic compartment of the local immune system. Chronic ulcerative colitis was associated with higher levels of CD19(+) B cells and CD3(+)CD4(+) T helper cells in the mesenteric lymph nodes, which was characteristic of adoptive immunity reactions and chronization of the inflammatory process.

Silver carp Hypophthalmichthys molitrix hatches from the envelope at phase 19 a day after fecundation (water temperature 26–28°C) with body length 5.2 mm. The formation of hypophysis begins 7–8 h after hatching of the embryo. The first chromophilic cells (acidophiles in adenohypophysis) appear at the age of 9 days; the first basophilic cells (thyrotropocytes) at the age of 17–20 days, when juveniles are at stage III. The gonadotropic function is formed in the ontogenesis of silver carp at the age of 40–45 days, i.e., almost a month after the appearance of elementary sexual cells in the gonads. The differentiation of gonadotropocytes in mesoadenohypophysis to two functionally active types of cells (central and peripheral) is also completed by this time.

The systemic injection of haloperidol (4 wk, 0.5 mg/kg/d) caused the increase of protein concentration and content, and the activity level of aminopeptidase in the cytoplasm of the neurons of associated type (layer III). The nucleus of these cells decreased both in sizes and in the content of proteins. In the neurons of efferent-projectory type (layer V), the decrease of studied peculiarities as compared with control level was observed. Tuftsin (300 micrograms/kg/d) injection after chronic haloperidol treatment causes the restoring action on changed parameters in sensomotor cortex. In caudate nucleus, tuftsin influence caused further reduction of neuron's cytoplasmic area and significant reduction in protein content. The received results testify to the morphobiochemical heterogenity of investigated brain structures, which is displayed both in the case of haloperidol treatment and in the case of its correction by neuropeptide tuftsin. Chronic haloperidol administration to animals can develop a model of certain symptoms and syndromes of parkinsonism. Its most pronounced manifestation is an imbalance in the neuromediator systems, especially the dopaminergic one (Mettler and Crandall, 1959; Colls, 1984; Funk et al., 1986). The research was performed in conjunction with the physiologists, whose experiments have shown that after chronic haloperidol administration, changes in animal behavior are developed that are typical for bradikinesia, and the motor regimen of integration is disturbed (Popova and Kachalova, 1991; Dovedova and Povova, 1993). Regulatory drugs, especially the tetrapeptide tuftsin, seem to correct such disturbances.

Studies were carried out on the model of regeneration of mechanically removed elasmoid scales. Regenerating scales were morphologically analyzed using light and electron microscopy. It was found that the cells responsible for regeneration of the elasmoid scale plates could be classified as osteogenic elements. Little differentiated preosteoblasts were detected in the connective tissue of dermis on day 3 of regeneration, while partially calcified plates underlaid osteoblasts on day 7. The scale cover was fully restored on day 14 and it took two days for each bone plate to be formed. Osteocytes, fully differentiated osteogenic elements, were found in the deepest regions of newly formed scales.

The process of aging is accompanied by significant derangements to brain function, which are expressed particularly as the well-known phenomenon of memory disturbance [4, 5]. Since memory functions are based on plastic rearrangements, in which the key role is played by metabolic processes, we elected to study the interactions between nerve cell activity and the state of protein biosynthesis during the formation of temporal associations in animals of different ages [3]. An interferometric method was considered appropriate in this regard as a method for estimating the dry weight of the cytoplasm and nucleus in neurons; this serves as a measure of their protein contents [1, 2]. The aim of the present work was to identify the relationship between the process of impressing the assimilation trace of a rhythm during the acquisition of an analog of a conditioned reflex to time in hippocampal neurons and their morphochemical parameters in elderly rabbits.

The rhythmic activity of CA1 hippocampal neurons was studied after the rhythmic (1-2 Hz) electrocutaneous forelimb stimulation (10-20 min) of 6-84-months-old rabbits. The spectral analysis of neuronal activity revealed the age-dependent decrease in ability to reproduce the rhythm of stimulation. The cytochemical data showed that the protein synthesis in the neurons under study also declined with age.

The investigation of protein (aminopeptidase activity, structured proteins) and of mediator metabolism (monoaminoxidase A and B activities, acetylcholine esterase, Ca(2+)-uptake) was carried out in rat brain motor structures. The study was performed during chronic L-DOPA and haloperidol administration that is under the conditions of hyper- and hypofunction of dopaminergic system. Some peculiarities and differences of sensomotor cortex and nucleus caudatus' reactions to the dysfunction of DA system were revealed at the cellular and subcellular levels. The results show the existence of high morpho-biochemical plasticity of brain structures mentioned above.