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Reparative proliferation and neurogenesis in the brain integrative centers after mechanical eye injury in an adult trout Oncorhynchus mykiss have been studied. We have found that proliferation and neurogenesis in proliferative brain regions, the cerebellum, and the optic tectum were significantly enhanced after the eye injury. The cerebellum showed a significant increase in the proliferative activity of the cells of the dorsal proliferative zone and parenchymal cells of the molecular and granular layers. One week after the injury, PCNA-positive radial glia cells have been identified in the tectum. We have found for the first time that the eye trauma resulted in the development of local clusters of undifferentiated cells forming so called neurogenic niches in the tectum and cerebellum. The differentiation of neuronal cells detected by labeling cells with antibodies against the protein HuC/D occurred in the proliferative zones of the telencephalon, the optic tectum, cerebellum, and medulla of a trout within 2 days after the injury. We have shown that the HuC/D expression is higher in the proliferative brain regions than in the definitive neurons of a trout. In addition, we have examined cell proliferation, migration, and apoptosis caused by the eye injury in the contra- and ipsilateral optic nerves and adjacent muscle fibers 2 days after the trauma. The qualitative and quantitative assessment of proliferation and apoptosis in the cells of the optic nerve of a trout has been made using antibodies against PCNA and the TUNEL method.

Expression of genes and heat shock proteins in normal intact retina of the Spanish Ribbed Newt Pleurodeles waltl was studied using polymerase chain reaction, Western blot hybridization, and immunohistochemistry. It was shown that the proteins HSP70 and HSP90, as well as their encoding transcripts of relevant genes, are constitutively expressed in eye tissues. These proteins were distributed differentially, and they were characterized by expression of different levels in the retina: HSP70 dominated in the external retina, while HSP90 dominated in the internal one, in particular, in Muller glial cells and the optic nerve. Transcripts and heat shock proteins HSP70 and HSP90 were also found in the retinal pigment epithelium and eye growth zone.

Diabetic Optical Neuropathy (DON) is the optical nerve damage induced by the Diabetes Mellitus. Optical nerve sufferings in Diabetes Mellitus were studied much less compare to the retinal changes. But according to the literature data, the DON has been detected in 7 to 24.3% of Diabetes Mellitus patients. That's why the investigators great interest refers to the optical nerve pathological changes pathways in Diabetes Mellitus studying. This article was focused to the up-to-date scientific views of the DON pathogenesis summarizing. Two basic ways of the DON pathogenesis were demonstrated: metabolic and vascular. The metabolic pathway was connected with the neural tissue damage induced by the diabetic changed metabolism. The vascular pathway was connected with the ischemia and endoneural blood flow malfunction.

The authors studied in an experiment the processes of a limited and controlled inflammatory reaction after modified laser cyclocoagulation (MLCC) and estimated the content of adenosine triphosphate (ATP) and guanosine triphosphate (GTP) in the retina and optic nerve. Hypotensive and trophic MLCC were carried out in 36 grey Shinshilla rabbits (36 eyes) by the standard procedure. Thirty-six pair eyes without MLCC served as a control. Biochemical studies yielded estimates of changes in the content of ATP and GTP in the hypotensive and trophic MLCC and control groups. The experiment showed an increase in the levels of ATP and GTP in nmole. The performed experimental studies proved that ocular exchange processes became activated and the content of ATP and GTP increased.

This work continues the studies of the proliferative ability of cells in the adult newt retina. The model of experimental detachment of the retina from pigment epithelium and two techniques to saturate the ocular tissues in vivo with precursors of DNA synthesis were used: (1) the method of repeated [3H]-thymidine labeling and subsequent autoradiographic analysis of semithin sections and (2) an original method for continuous labeling of thymidine analog bromodeoxyuridine and subsequent immunochemical detection. The data obtained confirm and extend our previous data on the localization of DNA-synthesizing cells in the neural retina and expose the pattern of S-phase cell accumulation after retinal detachment for each proliferation-competent cell population. In addition to cells in the growth zone of the retina, Muller glia, microglia, and minor cell population in the vitreal part of interneurons, DNA-synthesizing cells included astrocytes of the optic nerve and cells of its vascular network. Four weeks after detachment, the number of S-phase cells in the growth zone could reach 15-20%, while the above-mentioned DNA-synthesizing cells in the differentiated retina have low reproductive rate and could produce only one generation within the same period.

Retrograde staining of the Lymnaeae stagnalis retina with neurobiotin has shown that most photoreceptor cells send axons to optic nerve without intermediate contacts. A part of these photoreceptors have immunireactivity to glutamate that possibly provides synaptic transmission of visual signal to central neurons. Other photoreceptors stained through optic nerve seem to have different transmitter systems. In some retina cell, but not in optic nerve fibers, immunoreactivity to pigment-dispersing hormone has been revealed. In tissues surrounding the eye cup numerous serotonin-containing fibers are present, a part of them penetrating the retina basal layer. Some of them belong to central neurons responsible for efferent innervation of the pond snail eye. It is suggested that the serotoninergic innervation as well as the cell containing the pigment-dispersing hormone are included in the mechanism of regulation of light sensitivity of the mollusc eye.

Biological fluids from 146 patients with retrobulbar neuritis were examined for the biochemical, immunochemical and immunologic characteristics that mirror destructive processes in myelin and changes in the system of the cholinoglycine cycle which is one of the stages of the synthesis of myelin in the oligodendrocyte. In the majority of observations, the changes in these reactions of different directions and of varying intensity were revealed. Based on the data obtained the conclusion is made that part of the patients with retrobulbar neuritis may be attributed to multiple sclerosis since according to the laboratory findings, the demyelinating process occurring in them goes beyond optic nerves. Besides, it has been shown with special reference to retrobulbar neuritis that the primary affect, possibly of the viral nature, is likely to be localized in the oligodendrocyte, with myelin being involved in the process for the second time.

The effect of chemical modification on the binding of cholinergic ligands to nicotinic acetylcholine receptor from squid optical ganglion was studied. The existence of two chemically distinct subpopulations of binding sites was postulated. Subpopulation I contains, in all probability, Arg, Tyr and carboxyl groups critical for the binding of both ligands. Subpopulation II differs from the first one in the amino group present instead of Arg. The amino group important for the binding of d-tubocurarine alone was found in both subpopulations. The data obtained allow one to construct a model of nicotinic acetylcholine receptor cholinergic ligand recognition sites.