Blood vessels and immunoreactive substance P-containing nerve fibers in rat skin treated topically with clobetasol propionate, a corticosteroid.
After applying topically a cream (0.1 ml) containing corticosteroid (clobetasol propionate), on rat back skin, we examined the morphological alterations of blood vessels, substance P-containing nerve fibers, and cutaneous mast cells. After 3, 6, 10, 15, 30, and 60 min and 4 h, the skin treated was cut out with a sharp knife after killing the animals. The skin pieces were processed into conventional histological sections cut vertically and examined by staining immunohistochemically with anti-substance P serum, by staining with toluidine blue for mast cell granules, and by estimating morphometrically the average areas of vascular cavity and the number of substance P fibers in the dermis. In the dermis and subcutaneous tissue of untreated skin, we found many immunoreactive SP-containing nerve fibers and mast cells in close association. Three to ten min after the treatment, the average area of the vascular cavities steadily increased, and SP-positive fibers became less frequent in the dermis. In concomitant with those events, cutaneous mast cells discharged their granules. Thereafter, the average area of vascular cavities gradually decreased to a minimum at 4 h after the treatment. In contrast, both SP-containing fibers and mast cells reestablished their initial states after the same duration.
Oura
H
H
Department of Dermatology, School of Medicine, University of Tokushima, Japan.
Takeda
K
K
Daikoku
S
S
D000287:Administration, Topical; D000305:Adrenal Cortex Hormones / Q000008:administration & dosage* / Q000494:pharmacology; D000818:Animals; D002990:Clobetasol / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000494:pharmacology; D004730:Endothelium, Vascular / Q000187:drug effects; D008297:Male; D008407:Mast Cells / Q000187:drug effects; D009412:Nerve Fibers / Q000737:chemistry / Q000187:drug effects*; D051381:Rats; D017208:Rats, Wistar; D012867:Skin / Q000098:blood supply / Q000737:chemistry / Q000187:drug effects*; D013373:Substance P / Q000032:analysis / Q000187:drug effects*; D013997:Time Factors
D000305:Adrenal Cortex Hormones; D013373:Substance P; D002990:Clobetasol