RCS

Inbr. F22 (NIH 1989).

Colour: Pink-eyed, tan-hooded.

Genet. a, h, p.

Origin: Developed before 1965 by Sidman from stock obtained from Sorsby of the Royal College of Surgeons, London (Sidman and Pearlstein 1965). PETH is a presumed subline.

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Characteristics

Carries gene for retinal dystrophy, which causes over-production of rhodopsin and progressive loss of photoreceptor cells beginning in the third postnatal week. Cataracts develop in 24% of rats and there is a 4% incidence of microphthalmia. Hess et al (1985) found that the incidence of cataracts could be altered by the diet. A congenic strain RCS-p/+ has been developed in which the retinal dystrophy develops more slowly (LaVail and Battelle 1975, LaVail et al 1975, Essner et al 1979, Essner et al 1978). Mean litter size 6.8_0.1 (SEM). Body weight plateaus at 5-6 months at about 185g in females and 275g in males (La Vail et al 1975). Work with chimeric rats shows that the rdy gene acts in pigment epithelial cells rather than in photoreceptor cells (Mullen and LaVail 1976). During postnatal development of rod outer segments of normal animals, the number of phagosomes found 1-2 hrs. after the onset of light increases steadily until adult levels are reached by day 35. Phagosomes in RCS rats do not increase after day 15 (Tamai and O'Brien 1979). Electrical activity, rhodopsin content, rod structure and extracellular lamellae are retained longer when animals are reared in the dark (Dowling and Sidman 1962, Kaitz 1976, Kaitz and Auerbach 1979). Biochemical and cytological differences between the retinas of RCS and control animals have been reported by Lolly and Farber (1975,1976), Essner et al (1978), Essner and Gorrin (1979), Wiggert et al (1978), and Tamai and O'Brien (1979). Daily administration of 160 mg/kg of acetyl salicylic acid and ibuprofen leads to an appreciable retardation in the process of retinal degeneration (Elhifnawi et al, 1992). Instability of the lysosomal membrane in the pigment epithelium may initiate degeneration of photoreceptors and pigment epithelium (Elhifnawi et al, 1994).

Low relative heart weight in 10-week old males (3/23) (Tanase et al 1982).

Other papers using RCS include Thanos (1992), Atkinson et al, (1992), Thanos and Richter (1993), Elhifnawi (1995), Ueda and Steinberg, (1993)

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Atkinson E. G., Edelsten C., Kasp E., and Dumonde D. C. (1992) Experimental autoimmune uveoretinitis in the RCS rat - the influence of photoreceptor degeneration on disease expression. Brit. J. Ophthalmol. 76, 553-559.

Dowling J. E. and Sidman R. L. (1962) Inherited retinal dystrophy in the rat. J. Cell Biol. 14, 73-109.

Elhifnawi E. S., Kuhnel W., Orun C., Haug H., and Laqua H. (1992) The effect of cyclooxygenase inhibitors on the course of hereditary retinal dystrophy in RCS-rats. Annals of Anatomy-Anatomischer Anzeiger 174, 251-258.

Elhifnawi E., Kuhnel W., Elhifnawi A., and Laqua H. (1994) Localization of lysosomal-enzymes in the retina and retinal-pigment epithelium of RCS rats. Annals of Anatomy-Anatomischer Anzeiger 176, 505-513.

Elhifnawi E. (1995) Localization of cathepsin-D in rat ocular-tissues - an immunohistochemical study. Annals of Anatomy-Anatomischer Anzeiger 177, 11-17.

Essner E., Gorrin G., and Griewski R. A. (1978) Localization of lysosomal enzymes in retinal pigment epithelium of rats with inherited retinal dystrophy. Invest. Ophthalmol. Visual Sci. 17, 278-288.

Essner E. and Gorrin G. (1979) An electron microscopic study of macrophages in rats with inherited retinal dystrophy. Invest. Ophthalmol. Visual Sci. 18, 11-25.

Hess H. H., Knapke J. J., Newsome D. A., Westney I. V., and Wartofsky L. (1985) Dietary prevention of cataracts in the pink-eyed RCS rat. Lab. Animal Sci. 35, 47-53.

Kaitz M. and Auerbach E. (1979) Retinal degeneration in RCS rats raised under ambient light levels. Vision Res. 19, 79-81.

Kaitz M. (1976) The effect of light on brightness perception in rats with retinal dystrophy. Vision Res. 16, 141-148.

LaVail M. M. and Battelle B. (1975) Influence of eye pigmentation and light deprivation on inherited retinal dystrophy in the rat. Exp. Eye Res. 21, 167-192.

Mullen R. J. and LaVail M. M. (1976) Inherited retinal dystrophy: Primary defect in pigment epithelium determined with experimental rat chimeras. Science 192, 799-801.

Sidman R. L. and Pearlstein R. (1965) Pink-eyed dilution (p) gene in rodents: Increased pigmentation in tissue culture. Devel. Biol. 12, 93-116.

Tamai M. and O'Brien P. J. (1979) Retinal dystrophy in the RCS rat: In vivo and in vitro studies of phagocytic action of the pigment epithelium on the shed rod outer segments. Exp. Eye Res. 28, 399-411.

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.

Thanos S. and Richter W. (1993) The migratory potential of vitally labeled microglial cells within the retina of rats with hereditary photoreceptor dystrophy. International Journal of Developmental Neuroscience 11, 671-680.

Thanos S. (1992) Sick photoreceptors attract activated microglia from the ganglion- cell layer - a model to study the inflammatory cascades in rats with inherited retinal dystrophy. Brain Res. 588, 21-28.

Ueda Y. and Steinberg R. H. (1993) Voltage-operated calcium channels in fresh and cultured rat retinal- pigment epithelial-cells. Investigative Ophthalmology & Visual Science 34, 3408-3418.

Wiggert B., Bergsma D. R., Helmsen R., and Chader G. J. (1978) Vitamin A receptors: Retinoic acid binding in ocular tissues. Biochem. J. 169, 87-94.

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