title: The effect of X-ray irradiation upon the epithelial melanin unit of the hair bulb in hooded rat.
abstract: A marked increase in the quantity of pigment in the upper bulb, penetration of melanosomes into the papillae and vacuolisation of the bulb keratinocytes occurred as early as 4--6 h after irradiation with a dose 600--1200 R. Afterwards considerable hyperpigmentations appeared in the proximal segments of dystrophic and catagen hairs and melanin was found in the catagen columns and beyond them. In most animals within 4--6 h after irradiation occurred a distinct vacuolisation of the Malpighian layer and the granular layer became more prominent.
mesh_terms: D000818:Animals; D006197:Hair / Q000473:pathology / Q000528:radiation effects*; D007633:Keratins / Q000096:biosynthesis; D008544:Melanocytes / Q000528:radiation effects; D010858:Pigmentation / Q000528:radiation effects; D051381:Rats; D011919:Rats, Inbred Strains; D012867:Skin / Q000528:radiation effects; D014617:Vacuoles; D014965:X-Rays
chemical_list: D007633:Keratins