Sodium retention and hypertension after kidney transplantation in rats.

The present study was designed to investigate the development of blood pressure and renal sodium handling in recipients of renal grafts from adult stroke-prone spontaneously hypertensive rats (SHRSP), normotensive Wistar-Kyoto (WKY) rats, and borderline hypertensive F1 hybrids bred from SHRSP and WKY rats. Unilaterally nephrectomized F1 hybrids served as renal graft recipients. The second native kidney was removed 7 days after transplantation. Starting on the day of transplantation, renal graft recipients were put on a standard diet for 7 days followed by a low salt diet (0.18% salt) for 10 days and a high salt diet (1.8% salt) for another 14 days. In recipients of a renal graft from SHRSP donors, systolic blood pressure rose progressively from 140 +/- 4 mm Hg before to 190 +/- 7 mm Hg 4 weeks after transplantation. In contrast, in recipients of a renal graft from WKY rat donors, blood pressure fell during the same time from 139 +/- 7 mm Hg to 120 +/- 4 mm Hg. Blood pressure did not change significantly in recipients of a renal graft from F1 hybrid donors (132 +/- 4 versus 138 +/- 7 mm Hg). With transition from a low salt to high salt diet, all rats exhibited renal sodium retention. The accumulating amount of sodium retained by the renal graft was significantly higher in recipients of an SHRSP kidney than in recipients of a WKY rat kidney at all days on the high salt diet.(ABSTRACT TRUNCATED AT 250 WORDS)