MORPHOFUNCTIONAL TRANSFORMATIONS IN THE CORNEA OF A RABBIT WITH BURN DAMAGE OF THE LIMB

The aim of the study was an experimental investigation of morphological changes in the cornea of rabbits with different areas of thermal damage of the limb.

Material and methods. The work was carried out on 150 eyes of 75 rabbits, 60 of which comprised the experimental group and 15 – the control group. Damage to the limbus was carried out by diathermocoagulation using apparatus “eye diathermocoagulant DK-1”. Rabbits were withdrawn from the experiment at 3, 7, 15, 30 and 60 days. Reparative histogenesis in the cornea of the rabbit eye was studied using survey histological and immunohistochemical methods.

Results. The results of the study showed that the nature of the reparative processes in the anterior epithelium of the cornea differs significantly depending on the degree of damage to the limbal zone. If the ¼ area of the limb is damaged in the anterior epithelium of the cornea, the mitotic activity of the epithelium is activated in the preserved limb region. If the ½ area of the limb is damaged, these changes are more pronounced and persist for a longer time. When ¾ of the area of the limb and the entire limb is damaged, pronounced destructive changes occur in the anterior epithelium of the cornea, thickening and dilatation of the stroma, and a buildup of the conjunctiva on the cornea.

Conclusion. Damage of the quarter and half of the limb is accompanied by activation of the reparative ability of the undamaged limb, leading to epithelialization of damaged corneal areas. If more than half of the limbal region is damaged, activation of the proliferative activity of the epithelial cells of the limbic zone is insufficient to completely restore the damage to the cornea In this case, the regeneration of the anterior epithelium of the cornea occurred both at the expense of the cambial cells of the undamaged part of the limb, and due to the growth of the epithelium of the conjunctiva to the lesion zone. The obtained results confirm the significance of the limbus in the reparative histogenesis of the cornea.

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