Identification and measurement of beta-endorphin levels in the skin during induced hair growth in mice

We describe new and effective techniques for extracting proopiomelanocortin (POMC)-derived peptides from mammalian skin. Using this methodology (hot-acid extraction) and two independent HPLC-controIled RTA systems, we identify beta-endorphin peptide in mammalian skin and demonstrate significant hair cycle-dependent fluctuations in both the skin concentration and the in situ expression pattern of beta-endorphin (sebaceous glands) during the entire murine hair cycle. The observed anagen (growth phase)-associated increase in beta-endorphin concentration and its decline during the follicle involution (catagen) or resting (telogen) phase raise the possibility of a regulatory function of this neuropeptide in cyclic changes of skin physiology. (C) 1997 Elsevier Science B.V.