[Mitotic activity changes in the corneal epithelium of rats of different ages following exposure to pain].

A study was made of pain stimulus (amputation of 1/3 of the tail) on the mitotic activity in the corneal epithelium of 21-day fetuses, 1-, 3-, 4-, 5-, 7-, 10-, 15-, 20- and 25-day rats. In 45 minutes after the infliction of trauma no significant change was seen in the cornea of the fetuses and of the one-day-old ratlings. A gradual establishment of the reactive inhibition of mitoses in response to pain occurred between the 3rd and the 10th day of postnatal development. This reaction became more intense after the 10th day, reaching the maximum by the 25th day. Reactive inhibition of the mitotic activity was connected with the inhibition of the entrance of cells into mitosis.