Electrolyte and nitrogen distribution in whole fat-free skin and heat-separated corium and epidermis.

After our studies on the distribution of water, nitrogen and electrolytes in the whole skin, it was thought that the different layers of the skin should be investigated separately. The epidermis was therefore separated from the corium and the nitrogen and electrolyte distribution was determined in each of the layers In view of the fact that adequate literature on the methods for the separation of epidermis from dermis exists in the paper by Baumberger, Suntzeff and Cowdry (1), no formal review of the earlier work will be given. In choosing a method for the separation of epidermis from corium for chemical analyses, we have to be guided by many considerations such as loss of water; chemical change within the epidermis or dermis during the separation; or shifting of water and electrolytes from one layer to the other, previous to and during the separation. The method of separation that we used is not entirely satisfactory. In addition to the loss of water during the separation, there is a possibility of chemical change within the epidermis during the separation. The analytical data as well as the derived data presented here show that the corium layer of the skin has a chemical composition differing so radically from the epidermis that, when analyzed together, as they must be in whole skin analyses, the changes in the corium may mask changes or lack of changes in the epidermis. This report supplies chemical data on the whole skin, coriurn and epidermis. These data have been interpreted histochemically and are believed to provide at least a first approximation of (1) the relative mass of the two layers in the whole skin; (2) the amount of fibrillary material in each of the layers; and (3) the distribution of electrolytes in the layers.