Human hair follicles express CRH, Urocortin and CRH-R1 and CRH-R2. CRH and urocortin expression is detected in keratinocytes of the outer root sheath (ORS) and hair bulb pre-cortex, but only weakly in basal keratinocytes of the hair matrix (M). Only relatively undifferentiated melanocytes located in the peripheral and proximal matrix express CRH and urocortin. Hair follicle fibroblasts including follicular papilla (FP) cells and dermal sheath (DS) fibroblasts also expressed CRH and urocortin (a, b). A similar distribution of both CRH-R1 and CRH-R2 is observed, but the expression commonly exhibited a marked nuclear pattern, especially in ORS keratinocytes (c, d). Negative control incubated with an irrelevant primary antibody (e). Tissue source: 49 year old female.