Abstract

The effects of immunosuppressive drugs on epidermal cell mitotic activity and the proliferative response of epidermis following ultraviolet radiation (UVR) were tested. Hairless (Skh-hr 1) mice were treated with immunosuppressive drugs at equivalent clinical doses with or without concomitant UVR (290-400 nm). Epidermal parameters measured were mitotic index (Im), rate of entry into mitosis (Fm), flash labelling index (FLI), rate of entry into DNA synthesis (Fs) and DNA content (flow cytometric analysis). In non-irradiated skin, prednisolone therapy depressed both mitotic activity and DNA synthesis; azathioprine and cyclosporin A had no effect; cyclophosphamide therapy increased the Fm and FLI values. Following repeated doses of UVR, there were enhanced mitotic activity and DNA synthesis in epidermis. Prednisolone therapy moderately depressed both proliferative responses; cyclophosphamide enhanced mitotic activity; azathioprine and cyclosporin A had no effect on these responses. The significance of these findings in relation to potential for increased susceptibility of skin to UV-induced carcinogenesis is discussed.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.