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also greatly damaged Fig. 4. In medium containing hydrocortisone, the
epidermis showed more healthy cells, and did not become detached
from the dermis Fig. 5. The intercellular material and the cells in the
dermis were also considerably less damaged. Regeneration of the
irradiated epithelium occurred in both control and experimental
cultures but was accelerated in those kept with hydrocortisone. This was
due to the fact that more cells had survived in the epithelium and dermis
and the latter therefore provided a better substrate for the regenerating
epithelium.
Weissmann and Dingle (1962) found that irradiation of lysosomes
released an acid protease. If the lysosomes were isolated from animals
pretreated with hydrocortisone the enzyme was less readily liberated.
FIG. 4. Explant of foetal rat skin fixed 2 days after u.v. irradiation. The old epidermis forms a
blister above the denuded dermis and the deeper layers have disintegrated. Azan. x 105.
(From Weissmann and Fell, 1962.)
FIG. 5. Similar explant grown in medium containing hydrocortisone prior to u.v. irradiation.
The epidermis shows much less disintegration and has not formed a blister. Azan. x 105.
(From Weissmann and Fell, 1962.)