SR

Inbr.F54.

Colour: Albino,

Genet. c.

Origin: Rapp from a Sprague-Dawley outbred colony developed by LK Dahl, Brookhaven National Laboratories, Upton, New York, selected for resistance to salt-induced hypertension (Dahl et al 1962a,b). Also designated R/JR by Rapp (1984), and Dahl R by Mollegard, Copenhagen.

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Characteristics

Hypertension and vascular and renal lesions do not develop on a high (8%) salt diet (cf SS, see for example, Pontremoli et al, 1992). Mild hydronephrosis at 4 months of age that is probably genetically determined (Rapp and Dene 1985). Has mutant form of cytochrome P450(11-beta) (Matsukawa et al, 1993). Has lower transepithelial, unidirectional, sodium flux than SS and Sprague-Dawley which may be associated with its resistance to the development of hypertension on a high salt diet (Kudo et al, 1994).

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Dahl L. K., Heine M., and Tassinari L. (1962a) Effects of chronic excess salt ingestion. Evidence that genetic factors play an important role in susceptibility to experimental hypertension. J. Exp. Med. 115, 1173-1190.

Kudo L. H., Hawk C. T., and Schafer J. A. (1994) Sodium and water transport in cortical collecting duct of Dahl salt- resistant rat. American Journal of Physiology-Renal Fluid and Electrolyte Physiology 36, F583-F591.

Matsukawa N., Nonaka Y., Higaki J., Nagano M., Mikami H., Ogihara T., and Okamoto M. (1993) Dahls salt-resistant normotensive rat has mutations in cytochrome- P450(11-beta), but the salt-sensitive hypertensive rat does not. J. Biol. Chem. 268, 9117-9121.

Rapp J. P. and Dene H. (1985) Development and characteristics of inbred strains of Dahl salt-sensitive and salt-resistant rats. Hypertension 7, 340-349.

Rapp J. R. (1984) Characteristics of Dahl salt-susceptible and salt-resistant rats, in Handbook of Hypertension Vol. 4. Experimental and genetic models of hypertension (de Jong W., ed), pp. 287-295. Elsevier, Amsterdam, New York, Oxford.

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