Analysis of arterial pressure regulating systems in renal post-transplantation hypertension.
OBJECTIVE
To investigate if blood volume expansion, increased sodium retention, changes in neurohumoral arterial pressure control, or altered extrarenal resistance vessel function contribute to the development of renal post-transplantation hypertension.


METHODS
F1-hybrids (F1H) obtained from crossing spontaneously hypertensive rats (SHR) and Wistar-Kyoto rats received either an SHR or an F1H kidney graft. Groups consisted of 8-12 animals and were investigated between days 1 and 14 after renal transplantation in three sets of experiments including arterial pressure recordings, plasma volume measurements, metabolic studies, and small vessel myography.


RESULTS
Two days after completion of bilateral nephrectomy, arterial pressure was elevated by 15-20 mmHg in recipients of an SHR kidney, compared with syngeneically transplanted controls. There was no evidence for increased sodium and fluid retention during the early development of renal post-transplantation hypertension despite a 35% reduced creatinine clearance in recipients of an SHR kidney. The plasma renin-angiotensin-aldosterone system was similarly suppressed in both recipients of an SHR kidney and controls. The arterial pressure response to ganglionic blockade did not differ between groups and there was no evidence for changes in extrarenal resistance vessel function, which could be involved in the genesis of this form of hypertension.


CONCLUSIONS
None of the investigated mechanisms was altered in a way that might help to explain the rapid and consistent development of hypertension in recipients of an SHR kidney. We conclude that post-transplantation hypertension in recipients of an SHR kidney is due to mechanisms other than those investigated in the present study.
Grisk
Olaf
O
Department of Physiology, University of Greifswald, Karlsburg, Germany. grisko@uni-greifswald.de
Heukäufer
Matthias
M
Steinbach
Antje
A
Gruska
Sybille
S
Rettig
Rainer
R
D000450:Aldosterone / Q000097:blood; D000818:Animals; D015415:Biomarkers / Q000097:blood / Q000652:urine; D001794:Blood Pressure / Q000187:drug effects / Q000502:physiology*; D004195:Disease Models, Animal; D004231:Diuresis / Q000187:drug effects / Q000502:physiology; D004730:Endothelium, Vascular / Q000187:drug effects / Q000378:metabolism / Q000503:physiopathology; D005260:Female; D005730:Ganglionic Blockers / Q000494:pharmacology; D006977:Hypertension, Renal / Q000209:etiology* / Q000503:physiopathology*; D007668:Kidney / Q000098:blood supply / Q000378:metabolism / Q000503:physiopathology; D016030:Kidney Transplantation; D008297:Male; D008955:Models, Cardiovascular; D009318:Natriuresis / Q000187:drug effects / Q000502:physiology; D009569:Nitric Oxide / Q000378:metabolism; D010953:Plasma Volume / Q000187:drug effects / Q000502:physiology; D011183:Postoperative Complications / Q000209:etiology* / Q000503:physiopathology*; D051381:Rats; D011918:Rats, Inbred SHR; D011921:Rats, Inbred WKY; D012077:Renal Artery / Q000187:drug effects / Q000378:metabolism / Q000503:physiopathology; D012083:Renin / Q000097:blood; D012084:Renin-Angiotensin System / Q000187:drug effects / Q000502:physiology; D014655:Vascular Resistance / Q000187:drug effects / Q000502:physiology; D014664:Vasodilation / Q000187:drug effects / Q000502:physiology
D015415:Biomarkers; D005730:Ganglionic Blockers; D009569:Nitric Oxide; D000450:Aldosterone; D012083:Renin