PRL and disorder of pilosebaceous unit: Given the major endocrine functions of skin [22], [23], [24], [25], [26], a source and target of PRL [1], and that PRL is a potential player in skin and hair diseases [3], [4], [5], [6], [7], [27], [28], [29] a comprehensive analysis of the intracutaneous regulation of PRL and PRLR is required.