Fig. 1.
Increased expression of melanogenic paracrine cytokines and their receptors in uneven-toned skin. (A) Clinical appearance of uneven–toned skin on the upper arm of a Caucasian female subject. Scale bar=1 cm. (B) Clinical appearance of even–toned skin on the upper arm of another Caucasian female subject. Scale bar=1 cm. mRNA transcript levels of EDN1 (C), EDNRB (D), KITLG (E), KIT (F), POMC (G) and MC1R (H) were measured using TaqMan real-time PCR in epidermal sheets obtained from even-toned and uneven-toned skin. mRNA transcript levels were normalized to RPLP0 (ribosomal protein large P0). Relative amounts of each mRNA transcript in unevenly pigmented skin are expressed as a ratio against even-toned skin. Values represent means±s.d. from eight subjects. ***P<0.001; **P<0.01; *P<0.05 (Student's t-test).