Does Prolactin Play a Role in Skin Biology and Pathology?

The document from 1991 discusses the hypothesis that prolactin (PRL), a pituitary hormone known for its role in growth and osmoregulation of epithelial tissues and immunoregulation, may also play a significant role in human skin biology and pathology. It suggests that PRL could act as a neuroendocrine modulator of skin epithelial cell proliferation and the skin immune system by creating a 'prolactin-circuit' between the central nervous system and the skin. The hormone might affect skin cell growth through binding to specific skin receptors, modulating cytokine release, and stimulating somatomedin release by mesenchymal cells. The document also mentions the possibility of feedback signals from the skin influencing pituitary PRL release. The role of PRL in psoriasis and hair growth is used as models to support this theory, with clinical and experimental evidence discussed from a 'neuroimmune-dermatological' perspective.