Clopidogrel preserves whole kidney autoregulatory behavior in ANG II-induced hypertension.
This study tested the hypothesis that P2Y12 receptor blockade with clopidogrel preserves renal autoregulatory ability during ANG II-induced hypertension. Clopidogrel was administered orally to male Sprague-Dawley rats chronically infused with ANG II. After 14 days of treatment, whole kidney autoregulation of renal blood flow was assessed in vivo in pentobarbital-anesthetized rats using an ultrasonic flow probe placed around the left renal artery. In ANG II-vehicle-treated rats, decreasing arterial pressure over a range from 160 to 100 mmHg resulted in a 25 ± 5% decrease in renal blood flow, demonstrating a significant loss of autoregulation with an autoregulatory index of 0.66 ± 0.15. However, clopidogrel treatment preserved autoregulatory behavior in ANG II-treated rats to levels indistinguishable from normotensive sham-operated (sham) rats (autoregulatory index: 0.04 ± 0.14). Compared with normotensive sham-vehicle-treated rats, ANG II infusion increased renal CD3-positive T cell infiltration by 66 ± 6%, induced significant thickening of the preglomerular vessels and glomerular basement membrane and increased glomerular collagen I deposition, tubulointerstitial fibrosis, damage to the proximal tubular brush border, and protein excretion. Clopidogrel significantly reduced renal infiltration of T cells by 39 ± 9% and prevented interstitial artery thickening, ANG II-induced damage to the glomerular basement membrane, deposition of collagen type I, and tubulointerstitial fibrosis, despite the maintenance of hypertension. These data demonstrate that systemic P2Y12 receptor blockade with clopidogrel protects against impairment of autoregulatory behavior and renal vascular injury in ANG II-induced hypertension, possibly by reducing renal T cell infiltration.
Dept. of Physiology CA-3137, Georgia Regents Univ., 1120 15th St., Augusta, GA 30912. einscho@gru.edu.
David A
DA
Osmond
Shali
S
Zhang
Jennifer S
JS
Pollock
Tatsuo
T
Yamamoto
Carmen
C
De Miguel
Edward W
EW
Inscho
D000804:Angiotensin II / Q000494:pharmacology*; D000818:Animals; D000077144:Clopidogrel; D006973:Hypertension / Q000139:chemically induced* / Q000503:physiopathology; D007668:Kidney / Q000098:blood supply / Q000503:physiopathology*; D008297:Male; D058921:Purinergic P2Y Receptor Antagonists / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D058925:Receptors, Purinergic P2Y12 / Q000502:physiology*; D012079:Renal Circulation / Q000502:physiology*; D013929:Thromboxane B2 / Q000097:blood; D013988:Ticlopidine / Q000031:analogs & derivatives* / Q000494:pharmacology
D058921:Purinergic P2Y Receptor Antagonists; D058925:Receptors, Purinergic P2Y12; D000804:Angiotensin II; D013929:Thromboxane B2; D000077144:Clopidogrel; D013988:Ticlopidine
angiotensin II; autoregulatory response; clopidogrel; lymphocyte; purinergic P2Y receptors; thromboxane