title: Cardiac interstitial bradykinin and mast cells modulate pattern of LV remodeling in volume overload in rats.
abstract: In the current study, interstitial fluid (ISF), bradykinin (BK), and angiotensin II (ANG II) levels were measured using cardiac microdialysis in conscious, nonsedated rats at baseline and at 48 h and 5 days after each of the following: sham surgery (sham, n = 6), sham + administration of ANG-converting enzyme inhibitor ramipril (R, n = 6), creation of aortocaval fistula (ACF, n = 6), ACF + R (n = 6), and ACF + R + BK2 receptor antagonist (HOE-140) administration (n = 6). At 5 days, both ISF ANG II and BK increased in ACF rats (P < 0.05); however, in ACF + R rats, ISF ANG II did not differ from basal levels and ISF BK increased greater than threefold above baseline at 2 and 5 days (P < 0.05). Five days after ACF, the left ventricular (LV) weight-to-body weight ratio increased 30% (P < 0.05) in ACF but did not differ from sham in ACF + R and ACF + R + HOE-140 rats despite similar systemic arterial pressures across all ACF groups. However, ACF + R + HOE-140 rats had greater postmortem wall thickness-to-diameter ratio and smaller cross-sectional diameter compared with ACF + R rats. There was a significant increase in mast cell density in ACF and ACF + R rats that decreased below sham in ACF + R + HOE-140 rats. These results suggest a potentially important interaction of mast cells and BK in the cardiac interstitium that modulates the pattern of LV remodeling in the acute phase of volume overload.
authors.affiliation: Department of Medicine, Division of Cardiovascular Disease, Birmingham Veterans Affairs Medical Center, Birmingham, AL 35294, USA.
authors.forename: Chih-Chang
authors.initials: CC
authors.lastname: Wei
authors.forename: Pamela A
authors.initials: PA
authors.lastname: Lucchesi
authors.forename: Jose
authors.initials: J
authors.lastname: Tallaj
authors.forename: Wayne E
authors.initials: WE
authors.lastname: Bradley
authors.forename: Pamela C
authors.initials: PC
authors.lastname: Powell
authors.forename: Louis J
authors.initials: LJ
authors.lastname: Dell'Italia
mesh_terms: D000208:Acute Disease; D000804:Angiotensin II / Q000097:blood / Q000378:metabolism; D000818:Animals; D001011:Aorta; D001164:Arteriovenous Fistula; D001920:Bradykinin / Q000097:blood / Q000378:metabolism*; D002306:Cardiac Volume / Q000502:physiology; D002452:Cell Count; D053818:Chymases; D003243:Consciousness; D004195:Disease Models, Animal; D005110:Extracellular Space / Q000378:metabolism; D008407:Mast Cells / Q000166:cytology / Q000378:metabolism*; D017551:Microdialysis; D009206:Myocardium / Q000378:metabolism* / Q000473:pathology*; D007703:Peptidyl-Dipeptidase A / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D012697:Serine Endopeptidases / Q000378:metabolism; D014682:Vena Cava, Inferior; D020257:Ventricular Remodeling / Q000502:physiology*
chemical_list: D000804:Angiotensin II; D007703:Peptidyl-Dipeptidase A; D012697:Serine Endopeptidases; D053818:Chymases; D001920:Bradykinin