Luteinizing hormone/human chorionic gonadotrophin receptors in various epidermal structures

Two different monoclonal antibodies recognizing different epitopes were use d to study the localization of luteinizing hormone/human chorionic gonadotr ophin (LH/hCG) receptors in human skin. Immunolabelling was observed only i n the epidermis and derived structures but not in the dermis. The basal, sp inal and granular layers were stained, whereas no receptors were detected i n the nonnucleated horny cells. In the growing (anagen) hair, immunostainin g was found in the inner root sheath below the level of the sebaceous gland s and in the outer root sheath above this level. In the resting (telogen) h air, only the latter staining was observed. In the sebaceous glands, only t he thin cells close to the walls of the ducts were immunolabelled. In the e ccrine sweat glands, the external clear cells were stained in the secretory portion of the gland, whereas only the cells close to the lumen were label led in the ducts. The distribution of LH/hCG receptors was compared with th at of steroidogenic enzymes (side chain cleavage cytochrome P450, adrenodox in, 3-beta-hydroxy-5-ene steroid dehydrogenase Delta 5-Delta 4 isomerase, 1 7-hydroxylase cytochrome P450 and cytochrome P450 aromatase). Only partial overlaps were observed. The presence of LH receptor mRNA in the skin was co nfirmed by reverse transcription-polymerase chain reaction. Monoclonal anti bodies raised against the human follicle-stimulating hormone receptor faile d to detect the latter in the epidermal structures and in the dermis. The r ole of LH and hCG; in sl;in modifications occurring during pregnancy and af ter the menopause is unknown. These hormones may possibly act by regulating steroidogenic enzymes or by modulating cell growth and differentiation.