[Retinoprotective effects of Retinalamin studied in an experimental model of photochemical damage to rabbit retinas]. / Issledovanie retinoprotektornykh effektov retinalamina v eksperimental'noi modeli fotokhimicheskogo povrezhdeniya setchatki krolika.

Purpose - to investigate functional and morphological effects of peptide bioregulator (Retinalamin) in modeling of photochemical damage to rabbit retina. MATERIAL AND METHODS: The study was conducted on 36 rabbits (72 eyes) randomized into 4 equal groups: two experimental groups received parabulbar injections of Retinalamin («Geropharm¼, Russia) in each eye in dosages of 0.25 mg/kg in a course of 10 days starting from day 1 and day 10 of the experiment, respectively, and two control groups that received injections of normal solution with the same regimen. To simulate photochemical damage to the retina, exposure to light with a wavelength of 405 nm, a power density of 5 mW/cm2 and daily exposure time of 4 h was performed for 20 days. Multifocal and flicker 30 Hz electroretinogram (mfERG and fERG) were recorded, and histological studies of retina samples with quantitative assessment of retinal cells apoptosis by the TUNEL method were conducted before, as well as 10, 20 and 30 days after the start of light exposure. RESULTS: Ophthalmoscopic signs of light-induced retinal degeneration were revealed 6-10 days after start of exposure in all groups. When registering mfERG and fERG in all groups, there was a significant decrease in the amplitude of N1 and P1 peaks, retinal density of the bioelectric response of the P1 component, as well as the amplitude of fERG on days 10 and 20 after the beginning of light exposure (p<0.001 in comparison with the background values), and a slight increase in the indicators on day 30. Histological examination revealed a significant decrease in the number of cells in the outer nuclear layer and an increase in the proportion of apoptotic cells in the outer and inner nuclear layers on days 10 and 20 of the experiment, with a decrease on day 30 (after cessation of light exposure). Comparison of the groups receiving Retinalamin injections from days 1 or 10 of light exposure between themselves and the control groups revealed no significant differences in any of the studied parameters (p>0.05). CONCLUSION: No significant functional and morphological evidence of neuroprotective effects of Retinalamin were found in the model of photochemical damage to rabbit retinas.

Modeling of Retinal Degeneration.

We developed a model of retinal degeneration in rabbits based on exposure to light with a wavelength of 405 nm. This model allows reproducing structural and functional disorders in the central parts of the retina, including primarily degeneration of the outer layers of the retina (retinal pigment epithelium and layer of photoreceptor cells), and is designed to study the mechanisms of formation, progression and effectiveness of new drugs and methods of treatment of degenerative diseases of the retina.

[Multifocal electroretinography in the study of focal and diffuse damage to the rabbit retina]. / Mul'tifokal'naya elektroretinografiya v issledovanii ochagovykh i diffuznykh izmenenii setchatki krolika.

PURPOSE: To evaluate the possibility of using the system "Neuro-ERG" (with a module for multifocal ERG) in the study of focal and diffuse pathology in laboratory animals (rabbits). MATERIAL AND METHODS: Focal retinal damage was modelled in 5 eyes of 5 rabbits by singular laser pulses (532 nm, 100 ms, power 30, 60, 100, 150 and 200 mW) and diffuse retinal damage was modelled in 5 eyes of 5 rabbits by exposure to polychromatic light for 14 days (9500 lm, 6400 K, 230 mW/cm2, 8 h/day). The pair of eyes and areas of intact retina in the eyes with focal retinal damage were used for control. Multifocal electroretinography (mfERG) was recorded using the «Neuro-ERG¼ system (Neurosoft, Russia) before exposure, after 1 hour (in focal damage model), and 1, 7 and 14 days after exposure. In addition, three-time recording of mfERG was made before and after the experiments. Analysis included the amplitude and time characteristics of mfERG components, as well as the level of reproducibility of mfERG at each recording. RESULTS: In the modeling of focal damage of the rabbit retina, significant changes in mfERG (pattern stimulus consisted of 61 hexagons) were detected when the retinal damage area was more than 170 µm in diameter or more than 35% of the hexagon area in the pattern-stimulus. A significant moderate inverse correlation (0.52

[Acute ocular lesions after exposure to electromagnetic radiation of ultrahigh frequency (an experimental study)]. / Ostroe porazhenie organa zreniia élektromagnitnym izlucheniem sverkhvysokochastotnogo diapazona (éksperimental'noe issledovanie).

PURPOSE: To investigate the clinical and morphological manifestations of ocular lesions resulting from acute exposure to microwave radiation (MR). MATERIAL AND METHODS: Twenty-four rabbits were included in the study and divided into four equal groups according to MR exposure time (15, 30, 45, 60 s). The right eyes of rabbits were exposed to MR of 3.97 GHz and energy density of 1.0 W/cm2. The sham control group consisted of six animals. The exposed (right) and the paired (left) eye were studied for clinical and morphological changes, content of proinflammatory cytokines IL-1ß, IL-6 and TNF-α in the anterior chamber and in the vitreous body after exposure to MR. RESULTS: Significant dose-dependent changes in the structure of the exposed eye were revealed. Formation of microwave cataract was noted at the MR exposure time of 15 seconds and more. Partial or complete de-epithelialization, stromal edema, endothelial damage and inflammatory infiltration in the cornea, effusion of protein and cellular reaction in the aqueous humor were detected after MR exposure of 30, 45 and 60 seconds. Cellular reaction in the vitreous body was observed after exposure time of 45 and 60 seconds. Exposure to MR for up to 1 minute did not lead to visible clinical or morphological (traditional methods of examination) damage of the retina and optic nerve within 24 hours. Significantly higher content of proinflammatory cytokines IL-1ß, IL-6 and TNF-α in the aqueous humor and vitreous body was revealed in animals exposed to MR for 45 and 60 seconds. CONCLUSION: Acute exposure of the organ of vision to electromagnetic microwave radiation can lead to adverse dose-dependent effects not only in the lens, but also in other structures of the eye.

The Effect of Electromagnetic Fields of Extremely Low Frequency 30 Hz on Rat Ovaries.

We studied the effects of extremely low-frequency electromagnetic field on the ovaries in rats. The female rats were exposed to a 30 Hz sinusoidal magnetic field of 4 kA/m for 2 h per day for a period of 10 weeks, including the period of embryonic development. After the exposure, the duration of the estrous cycle and serum levels of luteinizing hormone, follicle stimulating hormone, progesterone, and estradiol E2 were measured in different phases of the estrous cycle and morphological changes in the ovaries were evaluated. Lower levels of follicle stimulating hormone in the proestrus and progesterone in the estrus phase were found; in the ovaries, the content of primordial follicles was lower than in the control. The exposure to electromagnetic field in the selected mode caused no significant defects in the structure and function of rat ovaries.

[The effectiveness of intraocular delivery of 5-fluoroquinolones for prophylaxis of intraocular infection].

The authors examined the possibility of the usage of ionic soft contact lenses for intraocular delivery of antibiotics for prophylaxis of intraocular infection in open combat trauma of the eyes during the stages of medical evacuation to the local military conflicts, as well as to the hospital before elective surgery. It is proved high efficiency lens, moxifloxacin and levofloxacin saturated to prevent inflammatory complications of the eyes.