Studies on the regeneration of the skin barrier and the changes in 32P incorporation into the epidermis after stripping

Abstract

SUMMARY: The epidermis of the rabbit ear was stripped and the effects on percutaneous absorption and 32P incorporation into lipid, TCA-sotuble, RNA and DNA fractions in the epidermis were studied for 21 days. Skin penetration by 14C-propylene glycol increased 300-fold immediately after stripping twenty times. Three to five days after stripping, penetration had returned almost to normal levels, but it required several additional days for the barrier function to become normal. The process of regeneration of the skin barrier paralleled the morphological changes in the epidermis but was inconsistent with the biochemical data. A significant increase in 32P incorporation was observed at 10 days, when the hyperplasia had disappeared and percutaneous absorption had returned to normal. The discrepancy between 32P incorporation and morphology or percutaneous absorption after stripping is discussed.