Rat strains

The direct histamine release evoked by several substances (e.g. codeine, dextran in certain rat strains or gelatine blood substitutes) led to the development of the concept of pseudo-allergic reactions by Paul Kallos [10]. 

Following chronic exposure, body weights of rats were similar to controls or up to 18% lower than controls at doses of 500 or 1,000 mg/kg/day, respectively (NCI 1976 NTP 1988, 1990). Among the different rat strains tested (ACI, August, Marshall, Osbome-Mendel), one gender was not consistently more sensitive to the... 

Chu, T., Kumagai, Y., DiStefano, E.W., and Cho, A.K., Disposition of methylenedioxymethamphetamine and three metabolites in the brains of different rat strains and their possible roles in acute serotonin depletion, Biochem. Pharmacol. 51(6), 789-796, 1996. 

The optical purities of the dihydrodiol metabolites formed in BaP metabolism by liver microsomes from Sprague-Dawley rats (1.14.15) are higher than those from liver microsomes from rats of Long-Evans strain (17). Repeated experiments in our laboratory using both rat strains indicate that small differences indeed exist (Table I). However, the percentages of R,R enantiomers are consistently higher than those reported by another laboratory (17). 

Caution The values used in the above equation are dependent on the test protocol, on the source of test animals, and on the rat strain. It is important to verify the above values whenever different conditions prevail and if necessary, to determine the values that would be applicable under the new conditions. 

Of all rat strains, the Brown Norway (BN) rat is used most frequently in relation to chemical-induced autoimmunity. This strain displays clinically manifested autoimmune disease following exposure to a number of chemicals. HgCl2 is the most scrutinized compound in the BN rat but D-penicillamine [6-8], gold-salts [9,10],hexachlorobenzene (HCB) [11-14] and recently, nevirapine [15], have all been shown to induce clinical effects. Captopril [7] and felbamate [16] appeared not to induce autoimmune effects in BN rats. 

Most previous work on rat MUPs has been conducted with inbred or relatively inbred laboratory rat strains that are likely to exhibit considerably reduced phenotypic variation relative to the wild population, as we see in mice. As an initial exploration of MUP expression, we analysed urine from nine wild-caught male rats captured from several different populations in northern UK by isoelectric focusing electrophoresis (IEF). The protein banding pattern was very similar between individuals, consisting of two major and several minor bands. Peptide mass... 

Type III (immune complex related disease) reactions have been demonstrated by the presence of proteinuria and immune complex deposits in the kidneys of the Brown-Norway, Lewis, and PVG/C rat strains. However, susceptibility to the deposition and the subsequent lesions (glomerulamephritis) are often variable and dependent on the strain (Bigazzi, 1985). For example, despite the appearance of clinical signs and proteinuria, after two-months administration of mercuric chloride, detectable levels of circulating antinuclear autoantibodies can no longer be observed in the Brown-Norway strain (Bellon et al., 1982). By contrast, in PVG/C rats administered mercuric chloride, immune complex deposition and antinuclear autoantibodies are present for longer periods of time however, proteinurea is not observed (Weeping et al., 1978). 

Brody AL, Mandelkern MA, Lee G, Smith E, Sadeghi M, Saxena S, Jarvik ME, London ED (2004) Attenuation of cue-induced cigarette craving and anterior cingulate cortex activation in bupropion-treated smokers a preliminary study. Psychiatry Res 130 269-281 Brower VG, Fu Y, Malta SG, Sharp BM (2002) Rat strain differences in nicotine self-administration using an unlimited access paradigm. Brain Res 930 12-20 Bruijnzeel AW, Markou A (2003) Characterization of the effects of bupropion on the reinforcing properties of nicotine and food in rats. Synapse 50 20-28... 

Mononuclear Cell Leukemia (MNCL) is unique to the rat, and is only common in the F-344 (common name Fischer rat) inbred rat strain, which is the strain used by the U.S. National Toxicology Program (NTP). Elevated incidences of MNCL have been observed in a number of chronic bioassays in the F-344 rat. The frequency differs between males and females, with an incidence in males around 50%, and an incidence in females around 30%, with a large variation from study to study. It has been shown for some genotoxic carcinogens that exposure does not lead to an increase in MNCL in the F-344 rat, while a number of substances, which are believed to be noncarcinogens,... 

The oral LDso was 713 mg/kg in male rats and 470mg/kg in females. (LDso values as low as 100 mg/kg have been reported for rats this range in values is attributed to different rat strains and from differences in the 1,3-DCP formulations used. ) Exposure to 1000 ppm for... 

Before selecting one of the different mous and rat strains available from commercial supphers for a given experiment, one has to carefully consider the rationale of the planned study (Andrews 1996 Crawley et al. 1997 Owen et al. 

Berrettini WH, Harris N, Ferraro TN, Vogel WH (1994) Maudsley reactive and non-reactive rats differ in exploratory behavior but not learning. Psychiatr Genet 4 91-94 Bizard DA, Altman HJ, Freedman LS (1982) The peripheral sympathetic nervous system in rat strains selectively bred for differences in response to stress. Behav Neural Biol 34 319-325... 

Dhabhar, F.S., McFwen, B.S., and Spencer, R.L. (1997) Adaptation to prolonged or repeated stress—comparison between rat strains showing intrinsic differences in reactivity to acute stress. Neuroendocrinology 65 360—368. 

Gomez, F, Lahmame, A., deKloet, E.R., and Armario, A. (1996) Hypothalamic-pituitary-adrenal response to chronic stress in five inbred rat strains differential responses are mainly located at the adrenocortical level. Neuroendocrinology 63 327-337. 

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