THE METABOLISM AND PERMEABILITY OF NORMAL SKIN

Abstract

This review is in 3 sections: Calvery reviews skin metabolism by recounting its chemical content with respect to protein and amino acids, glucose, glycogen, lactic acid, and other carbohydrates, and lipids; the composition of the sweat, and the changes in skin corresponding to vit. deficiencies. Only the skin of man and the higher mammals is considered, and only normal skin except in connection with vit. deficiencies. Draize reviews the histologic structures which affect skin permeability, confining himself to the normal-skin of higher mammals. He takes up the greasy outermost layer, the 5 layers of the epidermis, the electrophysical and electrochemical properties of the epidermis, the derma, the subcutis, cutaneous appendages, blood supply, and innervation. Laug discusses the various groups of substances (water, electrolytes, gases, fats, proteins, and amino acids, Hg and heavy metals, vits., sex hormones, sulfonamides, boric acid, iodine, salicylic acid) that have been shown to penetrate or not to penetrate the skin. He evaluates, where possible, the function of the vehicle, whether aqueous, lipoidal, or electrical, and the relation to permeability of the changes (keratolysis, hyper-emia, increased cellular activity, removal of skin substances) brought about in the skin by an applied substance.