Shear stress, imposed on the vascular endothelium by circulating blood, critically sustains vascular synthesis of nitric oxide (NO). Endothelial NO synthase (eNOS) activity is determined by heat shock protein 90 (HSP90), caveolin-1, and the cofactor tetrahydrobiopterin (BH4). To determine whether increased blood flow concomitantly upregulates eNOS and GTP cyclohydrolase I (GTPCH I, the rate-lim...

Stored cardiac pro-atrial natriuretic peptide (pro-ANP) is converted to ANP and released upon stretch from the atria into the circulation. Corin is a serin protease with pro-ANP-converting properties and may be the rate-limiting enzyme in ANP release. This study was aimed to clone and sequence corin in the rat and to analyze corin mRNA expression in heart failure when ANP release upon stretch i...

Rats with aortocaval fistula, an experimental model of congestive heart failure (CHF), display two distinct patterns of sodium excretion: some rats develop marked sodium retention and worsening edema with urinary excretion of sodium (UNaV) < 200 microEq per 24 hours, i.e., uncompensated CHF, whereas in others sodium balance rapidly returns to normal (UNaV > 1,400 microEq per 24 hours), i.e., co...

Diastolic dysfunction in volume-overload hypertrophy by aortocaval fistula is characterized by increased passive stiffness of the left ventricle (LV). We hypothesized that changes in passive properties are associated with abnormal myolaminar sheet mechanics during diastolic filling. We determined three-dimensional finite deformation of myofiber and myolaminar sheets in the LV free wall of six d...

BACKGROUND The role of nonhemodynamic cardiac trophic mechanisms differs not only between different models of cardiac hypertrophy but also within the same model for development versus maintenance of cardiac hypertrophy. Our previous studies pointed to a major role for the renin-angiotensin system (RAS) as a cardiac trophic stimulus in the remodeling of the heart in response to volume overload b...

OBJECTIVE Recently, deletion of specific genes by so called knock-out techniques has become important for investigating the pathogenesis of various diseases. This form of genetic engineering is widely performed in murine models. There are, however, only a limited number of mouse models available in cardiovascular pathology. The objective of this study, therefore, was to develop a new model of o...

Baroreceptor-heart rate reflex sensitivity is decreased in congestive heart failure. The reflex control of heart rate and sympathetic nerve activity in rats with chronic volume overload, an established model for moderate heart failure, is still unknown. Therefore, we investigated the regulation of humoral and neuronal sympathetic activity and the baroreflex control of heart rate and sympathetic...