A local potent glucocorticosteroid decreases the induction of galactosylhydroxylysyl glucosyltransferase in suction blisters but has no effect on basement membrane structures.

The effects of local glucocorticosteroid treatment on collagen biosynthesis and basement membrane components were studied in suction blisters in human abdominal skin. Pretreatment with clobetasol-17-propionate, applied three times a day for 4 days, did not affect the activity of galactosylhydroxylysyl glucosyltransferase (GGT) in fresh blisters but post-blistering treatment for 3 days with the steroid markedly inhibited the increase of this enzyme activity during the initial phases of re-epithelialization. The GGT activity was over 50% lower in steroid-treated blisters compared with control values. Protein concentrations and blister fluid volumes were also significantly decreased in healing 3-day blisters after steroid treatment. These results suggest that local glucocorticosteroid decreases either the synthesis of GGT or its release from the tissue into the blister fluid. The treatment did not affect the blister histology nor the early process of re-epithelialization. Immunohistochemically, type IV and V collagens and laminin of the basement membrane zone were similarly located in blisters of steroid-treated and placebo-treated skin, suggesting that local glucocorticosteroid does not affect the integrity of the basement membrane.