The effect of various constituants of the corneous layer on measurements of its elasticity.
Summary A new instrument has been developed which enables simultaneous determinations of the static and dynamic moduli of elasticity of the stratum corneum to be made. A systematic study of these mechanical parameters for various samples of human SC demonstrates the advantages of the dynamic measurement of the modulus of elasticity in evaluating the effect of treatments. The effect of treatment of thioglycollic acid (TA) and salicylic acid (SA) on the stratum corneum was studied by means of this technique and electron microscopy. TA markedly reduces the elastic modulus. Electron microscopy shows that horny cell structure is fully disorganized. On the contrary, SA treatment increases the elastic modulus without any noticeable changes on corneocytes. This last study confirms the preferential effect of SA on the intercorneocyte spaces.
Rasseneur
L
L
Départment de Physique, Laboratories de Recherche de L'Oréal, 1 Av. de St-Germain 93600-Aulnay-Sous-Bois, France.
Rigal
J
J
Leveque
J L
JL