The Studies on the Factors Related to Normal Hair Growth During Postnatal Growth Periods in C57BL/6N, Hairless and Alopecia Areata Mice Model

Lee, Moon Won; Oh, Chan Ho; Kwon, Jin; Song, Chang Ho; Lee, Chang Hyun

Abstract

We have examined the factors related to hair growth regulation during postnatal growth periods in C57BL/6N, hairless and alopecia areata mice model. We first studied the number, localization and granulation status of skin mast cells during postnatal growth periods by toluidine blue, alcian blue and H& E staining methods. We second studied immunoreactive density of neuropeptide (substance P, CGRP, CRF, CRF -receptor, CRF -binding protein) in skin by immunohistochemical methods. We third studied changes of subpopulation of splenocytes and thymocytes during postnatal growth periods in C57BL/6N, hairless and alopecia areata mice model by flow cytometry. The results were as follows : In C57BL/6N mice, the number of mast cells was decreased from 1day to 35 day during postnatal growth period. But skin of alopecia areata model mice in 21 day, the number of mast cells was more increased than that of normal skin. Immunoreactive density of neuropeptide (Substance P, CGRP, CRF, CRF -receptor, CRF -binding Protein) in skin during postnatal growth periods in C57BL/6N mice was weakly stained in 1, 3, 8 day, but immunoreactive density of neuropeptide was heavily stained in 35day and 21 day (no pigment). Splenic B and T lymphocytes were gradually increased with growth, and significantly increased in 29 days -old (hairless, pigment group) than 21 days -old (hairless, no pigment group) C57BL/6N mice. Especially, CD4 positive Th cells in splenic T lymphocytes were markedly increased. But thymic T lymphocytes were not shown any differences. In hairless mice, the number of mast cells was not changed from 3 day to 7 day, but more increased from 13day to 21day. Immunoreactive density of neuropeptide (substance P, CGRP, CRF) in skin during postnatal growth periods in hairless mice was weakly stained in 3, 7 and 13 day. but immunoreactive density of neuropeptide was heavily stained from 17 to 56 day. Splenic B and T lymphocytes were most highly increased in 13 days -old genetically hairless mice. And CD4 positive Th cells and CD8 positive Tc cells in splenic T lymphocytes were significantly increased. And also thymic Th lymphocytes were increased in 13 days -old and 17 days -old hairless mice. These experiment suggest that the factors related to hair loss were mast cells, immunoreactive density of neuropeptide (substance P, CGRP, CRF) and immune response during postnatal growth periods in C57BL/6N, hairless and alopecia areata mice model.