OM

Inbr. F100 (NIH 1989).

Colour: Albino.

Genet. c.

Origin: Heston 1946 from non-inbred Osborne-Mendel stock obtained from J White, to NIH at F10 (Hansen et al 1982).

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Characteristics

Spontaneous thyroid carcinoma 33% (Lindsey et al 1968). Adrenal cortical tumours 94% and pituitary tumours 8-18% at 18 months (Hansen et al 1973). In animals over 18 months Snell found adenomas or carcinomas of adrenal cortex 73% in males and 95% in females, pituitary tumours 25%, granulosa cell tumours of the ovary 33% in females. Animals were also relatively resistant to development of nephritis (Snell 1965). Poor survival to 2-years of age at 43% (rank 5/5) in males and 38% (rank 5/5) in females with relatively severe chronic renal disease and an intermediate level of hydronephrosis which may make the strain unsuitable for long-term toxicity studies (Solleveld and Boorman 1986). High blood pressure (3/23), reaching 154_1.0 (SEM) mmHg at 10 weeks of age (Tanase et al 1982). Mammary tumours 26-30%. High incidence of retinal degeneration in animals over 10 months (von Sallman and Grimes 1972, 1974). High systolic blood pressure (2/17) (Hansen et al 1973).

Becomes obese on a high fat diet (1/7) (Schemmel et al 1970, Buchanan et al, 1992). Enterostatin inhibited the uptake of high, but not low fat diets after an overnight fast (contrast strain S5B) (Okada et al, 1992). Intermediate breeding performance (8/12) and good litter size (4/12) (Hansen et al 1973). Very susceptible to chronic respiratory disease (Greenhouse et al 1991). Used in studies of effects of fluoride on tooth enamel and dental plaque by Shern and Couet (1979) and Shern et al (1979). High 10-week body weight in males (20/23) (Tanase et al 1982).

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Buchanan T. A., Fisler J. S., Underberger S., Sipos G. F., and Bray G. A. (1992) Whole-body insulin sensitivity in Osborne-Mendel and S5B/Pl rats eating a low-fat or high-fat diet. Am. J. Physiol. 263, R785-R789.

Hansen C. T., Judge F. J., and Whitney R. A. (1973) Catalogue of NIH Rodents. DREW Publ. No. 74-606. Department of Health, Education, and Welfare, Washington, D.C.: U.S.

Hansen C. T., Potkay S., Watson W. T., and Whitney R. A. Jr. (1982) NIH Rodents: (1980). Catalogue. NIH Publ. No. 83-606. Department of Health and Human Services, Washington, D.C.: U.S.

Lindsey S., Nichols C. W. Jr., and Chaikoff I. L. (1968) Naturally occurring thyroid carcinoma in the rat. Similarities to human medullary carcinoma. Arch. Pathol. 86, 353-364.

Okada S., York D. A., Bray G. A., Mei J., and Erlansonalbertsson C. (1992) Differential inhibition of fat intake in 2 strains of rat by the peptide enterostatin. Am. J. Physiol. 262, R1111-R1116.

Schemmel R., Mickelsen O., and Gill J. L. (1970) Dietary obesity in rats: Body weight and body fat accretion in seven strains of rats. J. Nutrit. 100, 1041-1048.

Shern R. J. and Couet K. M. (1979) Effects of stannous fluoride and tiodonium chloride on dental plaque in rats. J. Dental Res. 58, 1830-1835.

Snell K. C. (1965) Spontaneous lesions of the rat, in The Pathology of Laboratory Animals (Ribelin W. E. and McCoy J. R., eds), pp. 241-302. Charles C. Thomas, Springfield, Illinois.

Tanase H., Yamori Y., Hansen C. T., and Lovenberg W. (1982) Heart size in inbred strains of rats. Part 1. Genetic determination of the development of cardiovascular enlargement in rats. Hypertension 4, 864-872.

von Sallmann L. and Grimes P. (1972) Spontaneous retinal degeneration in mature Osborne-Mendel rats. Arch. Ophthalmol. 88, 404-411.

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INBRED STRAINS OF RATS
Updated 9 Apr. 1998
Michael FW Festing
MRC Toxicology Unit, Hodgkin Building,
University of Leicester, UK