Chemokine receptor 2b inhibition provides renal protection in angiotensin II - salt hypertension

Hypertension. 2007 Dec;50(6):1069-76. doi: 10.1161/HYPERTENSIONAHA.107.098806. Epub 2007 Oct 15.

Abstract

The present study was designed to determine whether chemokine receptor 2b (CCR2b) contributes to the development of renal injury in salt-sensitive angiotensin II (ANG) hypertension. Rats were infused with ANG and fed a high-salt diet (HS) for 14 days. Rats were divided into 4 groups: HS; HS administered the CCR2b antagonist, RS102895; Ang/HS hypertensive; and Ang/HS hypertensive administered RS102895. CCR2b inhibition slowed the progression of blood pressure elevation during the first week of ANG/HS hypertension; however, it did not alter blood pressure in the HS group. At 2 weeks, arterial pressure was not significantly different between ANG/HS and ANG/HS hypertensive rats administered RS102895. Renal cortical nuclear factor kappaB activity increased in ANG/HS hypertension compared with the HS group (0.11+/-0.006 versus 0.08+/-0.003 ng of activated nuclear factor kappaB per microgram of protein), and RS102895 treatment lowered nuclear factor kappaB activity in ANG/HS hypertension (0.08+/-0.005 ng of activated nuclear factor kappaB per microgram of protein). Renal tumor necrosis factor-alpha and intercellular adhesion molecule-1 expression increased, and Cyp2c23 expression decreased in ANG/HS hypertension compared with the HS group, and CCR2b inhibition reduced tumor necrosis factor-alpha and intercellular adhesion molecule-1 and increased Cyp2c23 expression. Histological immunostaining revealed increased renal monocyte and macrophage infiltration in ANG/HS hypertensive rats with decreased infiltration in rats receiving RS102895 treatment. Albuminuria and cortical collagen staining also increased in ANG/HS hypertensive rats, and RS102895 treatment lowered these effects. Afferent arteriolar autoregulatory responses to increasing renal perfusion pressure were blunted in ANG/HS hypertension, and RS102895 treatment improved this response. These data suggest that CCR2b inhibition protects the kidney in hypertension by reducing inflammation and delaying the progression of hypertension.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Angiotensin II / toxicity*
  • Animals
  • Chemokine CCL2 / physiology
  • Collagen / analysis
  • Cytochrome P-450 CYP2J2
  • Cytochrome P-450 Enzyme System / analysis
  • Hypertension / drug therapy*
  • Hypertension / etiology
  • Intercellular Adhesion Molecule-1 / analysis
  • Kidney / drug effects*
  • Macrophages / physiology
  • Male
  • NF-kappa B / metabolism
  • Rats
  • Rats, Sprague-Dawley
  • Receptors, CCR2 / antagonists & inhibitors*
  • Receptors, CCR2 / physiology
  • Sodium Chloride, Dietary / adverse effects*
  • Tumor Necrosis Factor-alpha / physiology

Substances

  • Ccl2 protein, rat
  • Chemokine CCL2
  • Cyp2c23 protein, rat
  • NF-kappa B
  • Receptors, CCR2
  • Sodium Chloride, Dietary
  • Tumor Necrosis Factor-alpha
  • Angiotensin II
  • Intercellular Adhesion Molecule-1
  • Collagen
  • Cytochrome P-450 Enzyme System
  • Cytochrome P-450 CYP2J2