A histometric and autoradiographic study of hydrocortisone action in cultured human epidermis.

Pieces of human skin maintained their viability, grew and differentiated for at least 10 days in chemically defined (serum-free) culture conditions. Physiological concentrations of hydrocortisone, added to the cultures, were shown to cause thinning of epidermis, which was due to decreased rate of epidermal proliferation. The relative volume of normal, orthokeratotic stratum corneum with underlying granular cells was increased concomitantly with epidermal thinning. The present findings show that even small concentrations of the hormone influence epidermal cell proliferation and suggest that hydrocortisone has a physiological role in keratinization. The possibility of using human skin culture in the assessment of the antiproliferative and atrophogenic action of synthetic glucocorticoids is discussed.