THE PERMEABILITY OF THE EPITHELIUM OF THE SKIN OF FETAL RATS DEMONSTRATED WITH A LANTHANUM-CONTAINING SOLUTION

  • 1 January 1983
    • journal article
    • research article
    • Vol. 136  (MAR) , 379-388
Abstract
Permeability of fetal rat skin between 18 and 21 days intrauterine life was investigated by immersing fetuses in lanthanum nitrate solution or injecting it subepidermally. Up to 18 days the epidermis was freely permeable from the basal surface but after 18 days it permeated only as far as the level at which membrane-coating granules were exocytosed. At all ages permeation from the outer surface was limited to the intercellular (tight) junctions between the cells of the periderm. Damage to the periderm at early ages resulted in complete penetration of the epidermis by La. Prior to the secretion of the epidermal permeability barrier at 18 days, the periderm was the principal barrier to penetration by La.