Therapeutic effect of an endothelin antagonist on ultraviolet B-induced pigmentation in guinea pigs / 中华皮肤科杂志

ABSTRACT

Objective To evaluate the therapeutic effect of endothelin antagonist on ultraviolet B (UVB)-induced pigmentation in guinea pigs.Methods A skin pigmentation model was established by UVB irradiation in guinea pigs.The modeled animals were divided into 3 groups to be treated with sodium chloride physiological solution (blank control group),an endothelin antagonist (endothelin antagonist group) and arbutin (positive control group),respectively.Before the UVB irradiation,as well as after 15-and 30-day UVB irradiation,Mexameter(R) MX 18 was used to detect the melanin index in the dorsal skin of guinea pigs.After 30-day consecutive treatment,melanin index,the number of melanocytes in the epidermis and melanin content were compared among the above 3 groups.Results After 30-day UVB irradiation,the melanin index in the 9 UVB-irradiated areas on the dorsal skin of guinea pigs significantly increased compared with that before the radiation (P ＜ 0.0001).After 30-day treatment with the 1‰ endothelin antagonist,the melanin index in the UVB-irradiated areas significantly decreased compared with that in the positive control group (P ＜ 0.0001).Melanin content index-1 (MCI-1) was significantly lower in the endothelin antagonist group than in the blank control group (P ＜ 0.05),while no significant difference in MCI-2 was observed among the 3 groups (P ＞ 0.05).Conclusion Topical application of the endothelin antagonist has a certain therapeutic effect on UVB-induced pigmentation in guinea pigs.