Experiments were performed on Rapp Dahl salt-sensitive (SS) rats (SS/JrHsdMcwi) bred at the Medical College of Wisconsin. Animal use and welfare procedures adhered to the National Institutes of Health Guide for the Care and Use of Laboratory Animals following protocols reviewed and approved by the Medical College of Wisconsin Institutional Animal Care and Use Committee. At the age of 7.5 weeks the rats were anesthetized with inhalation of 2.5% isoflurane in 0.5 l/min O2 flow. We used two approaches to register blood pressure. To study effects of salt intake (Figure 1), DSI telemeters (#TA11 PA-C40, Data Sciences International, St. Paul, MN) were installed in femoral arteries and affixed in a subcutaneous pocket in the loin area. Animals in individual cages were placed on an RPC-1 Transceiver interfaced via PhysioTel controller to computer equipped with the Ponemah software package.