Back to Search
Start Over
Ultraviolet radiation-induced skin tumors in a South American opossum (Monodelphis domestica)
- Source :
- Veterinary pathology. 28(1)
- Publication Year :
- 1991
-
Abstract
- A total of 19 male and 21 female South American opossums ( Monodelphis domestica) were exposed to 250 J/m2 ultraviolet radiation from FS-40 sunlamps (280-400 nm) three times weekly for 70 weeks. The backs of the opossums were shaved as necessary to remove hair. In order to prevent photoreactivation of ultraviolet radiation-induced pyrimidine dimers by the light-dependent photolyase enzyme of the opossum, ultraviolet radiation-exposed opossums were housed under red lights (600-800 nm). The opossum photolyase requires light in the 320-450 nm range for its activity. Twenty-nine control opossums (14 males and 15 females) were irradiated by fluorescent lights with emission spectra primarily in the visible light range (320-700 nm); these control opossums were also housed under red lights, and their backs were also shaved to remove hair. No skin tumors were observed in control opossums, while ultraviolet radiation-exposed opossums developed a variety of hyperplastic and neoplastic skin lesions on the backs and on a single ear. Hyperplastic lesions included foci of epithelial hyperplasia, dermal fibroplasia, and focal proliferation of dermal melanocytes. A total of 20 ultraviolet radiation-exposed opossums (50%) developed skin tumors, and 13 opossums (32.5%) had more than a single tumor. Epithelial tumors included 25 papillomas, four keratoacanthomas, seven carcinomas in situ, three microinvasive squamous cell carcinomas, two invasive squamous cell carcinomas, and a single basal cell tumor. Ten dermal spindle cell tumors also occurred; most of these appeared to be fibrosarcomas. Two benign melanomas and one malignant melanoma were observed.
- Subjects :
- 0301 basic medicine
Male
Pathology
medicine.medical_specialty
animal structures
Neoplasms, Radiation-Induced
Skin Neoplasms
Light
040301 veterinary sciences
Ultraviolet Rays
Longevity
Pyrimidine dimer
Monodelphis domestica
0403 veterinary science
03 medical and health sciences
Opossum
medicine
Animals
Fibrosarcoma
Photolyase
Ultraviolet radiation
Melanoma
Skin
Hyperplasia
integumentary system
General Veterinary
biology
Papilloma
urogenital system
04 agricultural and veterinary sciences
Opossums
biology.organism_classification
medicine.disease
Keratoacanthoma
030104 developmental biology
Carcinoma, Basal Cell
Carcinoma, Squamous Cell
Female
hormones, hormone substitutes, and hormone antagonists
Carcinoma in Situ
Subjects
Details
- ISSN :
- 03009858
- Volume :
- 28
- Issue :
- 1
- Database :
- OpenAIRE
- Journal :
- Veterinary pathology
- Accession number :
- edsair.doi.dedup.....51e6a91c916587d7474e4500e795c6f6