Effects of Subentaneous Injection of?-MSH on Alexandrite Laser Hair Removal in a Mouse Model / 中华皮肤科杂志

ABSTRACT

Objective To study the result of Alexandrite laser hair removal after subcutaneous in-jection of?-MSH in anagen-induced C57BL6mice.Methods Hair shafts were depilated by wax/resin mix-ture to induce hair follicles from telogen to anagen in60C57BL6mice.The mice were randomly divided in-to groups A,B,C and D.Groups A and B were injected with0.5mg/kg and0.25mg/kg of?-MSH,respec-tively,on the back skin subcutaneously once a day.Group C was injected with the same dose of normal saline.Group D was treated as blank control.Groups A,B and C were exposed to Alexandrite laser on ana-gen(substageⅣ).Biopsies were taken before treatment and0.5h,2and28days after treatment.Speci-mens were stained with Masson-Fontana method before treatment,and with haematoxylin and eosin after treatment.The cutaneous response was observed after laser hair removal.Hair regrowth was assessed28days after treatment.Results The mean gradation value of folliclar melanin was increased in the test groups than that in control group before laser hair removal.Extent of folliclar damage and cutaneous adverse reaction af-ter laser treatment was more severe in test groups than those in control group.Hair regrowth was less obvious in test groups than that in control group,while local hyperpigmentation was increased in test groups than that in control group28days after treatment.No scarring was observed in3groups.Conclusion Subentaneous injection of?-MSH could increase melanin of the hair,decrease hair regrowth,and enhance local pigmenta-tion after laser hair removal in anagen-induced C57BL6mice.