Initial Damage Produced by a Single 15-Gy X-Ray Irradiation to the Rat Calvaria Skin

The study examined the effects of a single 15-Gy x-ray irradiation on the calvaria skin of 25 Wistar rats, divided into 5 groups. It found that irradiation led to temporary atrophy in sebaceous glands and hair follicles and altered collagen fibers to an amorphous form, with a temporary predominance of type I collagen fibers on days 9 and 14. Despite these changes, there was no significant inflammatory response, cell proliferation, or fibrosis in the dermis. The number of MMP-9-expressing cells decreased, indicating reduced extracellular matrix remodeling. The findings highlighted the unique response of calvaria skin to radiation, differing from other skin regions.