Atrial natriuretic peptide concentration in dogs with congestive heart failure, chronic renal failure, and hyperadrenocorticism.

The function of atrial natriuretic peptide (ANP) is claimed to be control of salt and water homeostasis, and thus, the hormone may be involved in the pathogenesis of certain diseases with impaired volume regulation. We, therefore, studied plasma ANP concentration in dogs with chronic renal failure, congestive heart failure, and hyperadrenocorticism. Dogs with chronic renal failure had twofold higher plasma ANP concentration (16.2 +/- 5.8 fmol/ml), compared with healthy dogs (8.3 +/- 3.5 fmol/ml). An even more distinct increase (sixfold) of plasma ANP concentration was found in dogs with congestive heart failure (52.9 +/- 29.7 fmol/ml). In contrast, dogs with hyperadrenocorticism did not have high ANP plasma concentration (5.5 +/- 2.0 fmol/ml). High-performance liquid chromatographic analysis of plasma from dogs with congestive heart failure indicated that, in addition to the normal circulating form of ANP (99-126), the unprocessed precursor ANP (1-126) is detectable in the circulation. These qualitative and quantitative alterations of plasma ANP concentration in dogs further suggest involvement of this peptide in the development and/or maintenance of diseases associated with impaired volume regulation.