RESOLUTION OF POSTTRANSPLANT HYPERTENSION AFTER LIVER-TRANSPLANTATIONDESPITE IMPAIRED GLOMERULAR-FILTRATION

Hypertension developing after transplantation is characterized by wide spread vasoconstriction including the kidney. Late resolution (mean, 2 9 +/- 4 months) of posttransplant hypertension has been observed in 15 (Group I) of 278 subjects monitored after liver transplantation. Thes e studies were undertaken to define the systemic and renal changes ass ociated with resolution, as compared with a group matched for age, sex , and time after transplant who remained hypertensive (Group II; N = 1 5) or a group who never developed hypertension (Group III; N = 23). Bl ood pressure during resolution paralleled changes in the systemic resi stance index, which fell from 3,052 +/- 548 to 1,872 +/- 205 dyne/s.cm (5)/m(2) (P < 0.01). GFR and RBF remained low, despite the resolution of hypertension, and renal vascular resistance did not change. Circula ting endothelin levels remained above normal in all transplant recipie nts (Group I, 11.9 +/- 3.0 versus normal subjects, 7.0 +/- 1.1 pg/mL; P < 0.05), and urinary prostacyclin excretion was suppressed (880 +/- 120 versus 2,247 +/- 187 ng/day; P < 0.01). No hormonal differences we re apparent between transplant groups. These results demonstrate the c apacity for systemic vasodilation to occur after transplantation, inde pendent of vascular tone in the kidney. They further suggest that rena l vasoconstriction and impaired GFR alone are not sufficient to explai n de novo hypertension after transplantation.