Open AccessChanges in renal vessels following the long-term administration of an angiotensin II receptor blocker in Zucker fatty rats
Author(s) -
Kazushige Nakanishi,
Yohko Nagai,
Honglan Piao,
Tatsuo Akimoto,
Harubumi Kato,
Nadezhda Yanakieva-Georgieva,
Yukio Ishikawa,
Kastunori Yoshihara,
Kinji Ito,
Nobuaki Yamanaka,
Takashi Oite
Publication year - 2011
Publication title -
jraas. journal of the renin-angiotensin-aldosterone system/journal of the renin-angiotensin-aldosterone system
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.457
H-Index - 46
eISSN - 1752-8976
pISSN - 1470-3203
DOI - 10.1177/1470320310387844
Subject(s) - afferent arterioles , olmesartan , medicine , endocrinology , angiotensin receptor , proteinuria , angiotensin ii , blood pressure , kidney , chemistry
The nephro-protective effects of angiotensin II receptor blockers (ARBs) are widely known; however, there are few reports of long-term effects focusing on the renal vessels. We studied afferent arteriolar changes induced by the long-term administration of an ARB. Materials and Methods: Thirty-two 6-week-old male Zucker fatty rats (ZFRs) were divided into following four groups ( n = 8 in each): ZFR Group and ZFR+High Group fed a standard or high-salt diet, respectively; ZFR+ARB Group and ZFR+High+ARB Group fed a standard or high-salt diet with ARB (Olmesartan, 5 mg/kg/day), respectively. Blood pressure, proteinuria, morphological examinations and glomerular haemodynamics in vivo were studied. Results: Marked proliferative changes in the afferent arteriolar smooth muscle cells (SMCs) were frequently observed in the two groups given ARBs; in the ZFR+ARB group (77.3±10.3%) compared with the two groups without ARB (1.7%, p < 0.005; 1.2%, p < 0.0005) and 37.4±15.6% in the ZFR+High+ARB group. Proteinuria markedly decreased in the groups treated with ARBs, but the glomerular erythrocyte velocities showed no differences. Conclusions: Our findings indicate that long-term ARB administration induced unusual proliferative changes in SMCs of afferent arterioles of ZFRs. These changes could narrow arteriolar lumens and reduce intraglomerular pressure, but they could cause also irreversible damage to the arterioles.