Shared maternal influences in the development of high blood pressure in the spontaneously hypertensive (SHR) and Dahl salt-sensitive (SS/Jr) rat strains.
The influence of maternal environment on the development of high blood pressure in spontaneously hypertensive (SHR) and Dahl salt-sensitive (SS/Jr) rats was examined using the technique of reciprocal cross-fostering. Previous experiments from this laboratory demonstrated that adult blood pressures of the SHR and SS/Jr strains were significantly attenuated when hypertensive-strain pups were fostered to a dam of the respective normotensive control strain during the preweaning period. In this study, SHR and SS/Jr pups were assigned to either a cross-fostered (fostered to a dam of the opposite hypertensive strain) or control-reared condition within 24 h of birth. Adult resting blood pressures were similar in control and cross-fostered SHR rats and in control and cross-fostered SS/Jr rats. Heart rates and heart, adrenal, and kidney weights were also similar in control and cross-fostered rats of each strain. However, body weights of SHR rats reared by an SS/Jr dam were somewhat lower compared to control-reared SHR rats. These data indicate that the maternal environments provided by SHR and SS/Jr mothers are similar in some way such that they permit the development and full expression of the hypertensive phenotype in both same-strain and opposite-strain pups.
Murphy
C A
CA
Department of Psychology, University of Virginia, Charlottesville 22901.
Fields-Okotcha
C
C
McCarty
R
R
D000818:Animals; D001794:Blood Pressure / Q000235:genetics; D005260:Female; D005786:Gene Expression Regulation / Q000502:physiology*; D006339:Heart Rate / Q000235:genetics; D006973:Hypertension / Q000235:genetics*; D008297:Male; D008425:Maternal Behavior; D010641:Phenotype; D051381:Rats; D011918:Rats, Inbred SHR; D011919:Rats, Inbred Strains; D012931:Social Environment; D013045:Species Specificity