Relative roles of endothelin-1 and angiotensin II in experimental post-ischaemic acute renal failure.
BACKGROUND
The relative roles of endothelin (ET)-1 and angiotensin (ANG) II in post-ischaemic acute renal failure (ARF) have not been fully established so far. With the aim of contributing to this goal, we assessed in this study the effect of ANG II and ET-1 blockade on the course of post-ischaemic-ARF.


METHODS
Anaesthetized Wistar rats received i.v. either bosentan (a dual ET receptor antagonist; 10 mg/kg body weight) or losartan [ANG II type 1 (AT(1)) receptor antagonist; 5 or 10 mg/kg body weight] or both, 20 min before, during and 20 min after ischaemia. Rats in the control group received the vehicle via the same route. Survival and renal function were monitored up to 8 days after the ischaemic challenge, while haemodynamic parameters were measured 24 h after ARF.


RESULTS
Our results demonstrate that bosentan treatment has a more beneficial effect on experimental ARF than losartan. The survival rate was remarkably higher in bosentan-treated rats than in both rat groups treated with losartan. In the ARF group treated with bosentan, renal blood flow (RBF) was increased by 129% in comparison with the untreated ARF group, whereas in the losartan-treated ARF groups, RBF was only approximately 35 or 38% higher than in control ARF rats. The glomerular filtration rate was markedly higher in bosentan-treated rats than in all other ARF groups on the first and second day after ischaemia. Tubular cell injury was less severe in bosentan-treated rats than in the control ARF rats, but in losartan-treated groups it was similar to that in the ARF group. Concurrent blockade of both ET and AT(1) receptors did not improve ARF because this treatment induced a marked decrease in blood pressure.


CONCLUSIONS
These results suggest that ET-1 blockade is more efficient in improving the early course of post-ischaemic renal injury than ANG II inhibition, and that blockade of ET-1 might be effective in prophylaxis of ischaemic ARF.
Jerkić
Mirjana
M
Instituto Reina Sofía de Investigación Nefrológica, Departamento de Fisiología y Farmacología, Universidad de Salamanca, Avenida Campo Charro s/n, 37007 Salamanca, Spain.
Miloradović
Zoran
Z
Jovović
Durddica
D
Mihailović-Stanojević
Nevena
N
Elena
Juan Vicente Rivas
JV
Nastić-Mirić
Danica
D
Grujić-Adanja
Gordana
G
Rodríguez-Barbero
Alicia
A
Marković-Lipkovski
Jasmina
J
Vojvodić
Srećko B
SB
Manero
Marta Vicens
MV
Prieto
Marta Pérez
MP
López-Novoa
José Miguel
JM
D058186:Acute Kidney Injury / Q000503:physiopathology* / Q000628:therapy; D000804:Angiotensin II / Q000187:drug effects / Q000502:physiology*; D057911:Angiotensin Receptor Antagonists; D000818:Animals; D000959:Antihypertensive Agents / Q000008:administration & dosage; D000077300:Bosentan; D065128:Endothelin Receptor Antagonists; D019332:Endothelin-1 / Q000187:drug effects / Q000502:physiology*; D007262:Infusions, Intravenous; D007668:Kidney / Q000098:blood supply; D019808:Losartan / Q000008:administration & dosage; D008297:Male; D023421:Models, Animal; D051381:Rats; D017208:Rats, Wistar; D015427:Reperfusion Injury / Q000503:physiopathology* / Q000628:therapy; D013449:Sulfonamides / Q000008:administration & dosage
D057911:Angiotensin Receptor Antagonists; D000959:Antihypertensive Agents; D065128:Endothelin Receptor Antagonists; D019332:Endothelin-1; D013449:Sulfonamides; D000804:Angiotensin II; D019808:Losartan; D000077300:Bosentan