American Journal of Hypertension 1 Brief CommuniCations

It is well known that hypertension and target organ dam-age in spontaneously hypertensive rats (SHRs) is aggra-vated by treatment with NG-nitro-L-arginine methyl ester (L-NAME).1 A previous study indicated that kidney dam-age and reduced life-span in L-NAME–treated SHRs is further aggravated by transfer of rat chromosome (RNO) 6 from inbred Munich Wistar Frömter (MWF) rats into the SHR background.2 MWF rats develop mild hypertension and severe kidney disease with progressive albuminuria with age that is related to an interaction between multiple quantitative trait loci.3 Interestingly and surprisingly, how-ever, although proteinuria is aggravated in MWF rats dur-ing long-term treatment with L-NAME for 18 weeks, this intervention is very well tolerated in the original MWF strain with normal survival and no blood pressure increase in these rats.2 Taken together, these findings suggest that genetic variants affect the sensitivity and resistance to L-NAME treatment in the SHR vs. MWF comparison. In this study, we thus set out to test whether transfer of RNO8 from MWF into the SHR background affects susceptibility to L-NAME observed in this strain