Ventricular function and natriuretic peptides in sequentially combined models of hypertension

Abstract

Hemodynamic parameters and natriuretic peptide levels were evaluated in cardiac hypertrophy produced by sequentially applied renovascular (RV) and deoxycorticosterone acetate-salt (DS) models of hypertension. We studied hypertensive rats by RV or DS treatment at 2 and 4 wk, as well as by the combination of 2 wk of each treatment in an inverse sequence: RV 2 wk/DS 2 wk (RV2/DS2) and DS 2 wk/RV 2 wk (DS2/RV2). The in vivo cardiac function, interstitial fibrosis, and synthesis and secretion of types A (ANP) and B (BNP) natriuretic peptides were monitored in hypertensive models compared with their corresponding sham (Sh2, Sh4). There were no differences in relaxation parameters among RV or DS groups and combined treatments. Left ventricular +dP/dt(max) increased only in RV4 (P < 0.01 vs. Sh4), and this increase was abolished in RV2/DS2. Interstitial collagen concentration increased after 4 wk in both RV4 and RV2/DS2 groups. Although there were no changes in collagen concentration in either DS2 or DS4 groups, clipping after 2 wk of DS (DS2/RV2) remarkably stimulated interstitial fibrosis (P < 0.01 vs. DS2). Plasma BNP increased in RV treatment at 4 wk (P < 0.001 vs. Sh4), but not in DS. Interestingly, RV applied after the 2 wk of DS treatment induced a marked increase in BNP levels (P < 0.001 vs. Sh4). In this regard, plasma BNP appears to be a reliable indicator of pressure overload. Our results suggest that the second stimulus of mechanical overload in combined models of hypertension determines the evolution of hypertrophy and synthesis and secretion of ANP and BNP.

Circulating plasma serine208‐phosphorylated troponin T levels are indicator of cardiac dysfunction

“…In summary, P-Ser 208 -TnT with 94.7% sensitivity and 87.5% specificity was considered the best predictor of LV remodelling post-MI, suggesting the importance of P-Ser 208 -TnT as a new biomarker in HF (Table 2). These data are in accordance with previous publications showing that BNP and TIMP-1 plasma levels are also associated with severity of hypertension and not specifically to HF [19, 25, 26]. …”

“…In renovascular hypertension, circulating BNP levels were found to be significantly increased [25]. Comparison of the normotensive strain, WKY and the hypertensive strain, SHR showed a threefold increase in circulating BNP levels in SHR rats, which were also enhanced by DOCA-salt treatment [26].…”

Deletion of interleukin-6 prevents cardiac inflammation, fibrosis and dysfunction without affecting blood pressure in angiotensin II-high salt-induced hypertension

“…MCSA was measured by computer-based planimetry and averaged using the data obtained from all the photographs. The interstitial collagen fraction (ICF) was calculated as the ratio of the collagen area to the entire area of an individual section, which is the sum of the areas representing the myocytes and the interstitial space [15–17]. …”

Periodontal Pathogen Aggregatibacter actinomycetemcomitans Deteriorates Pressure Overload-Induced Myocardial Hypertrophy in Mice

“…4) The myocardial mRNA levels of tissue inhibitor of matrix metalloproteinase (TIMP)-1 and -2 were also significantly elevated. 5) Brain natriuretic peptide (BNP) is known to be a marker for volume and pressure overload 6) and its level increased in documented left ventricular diastolic dysfunction. 7) Periodontitis is a chronic inflammatory disease caused by gram-negative anaerobic bacteria, that results in bone resorption, destruction of the connective tissue, and loss of teeth.…”