Abstract
We examined the imunohistochemical distributions of natriuretic peptide receptor (NPR)-A, -B and -C that bind with natriatetic peptide hormones A, B and C using specific antibodies against human antigens in four healthy crossbreed young canine and feline cardiac tissues. Cross-immunities between antigens and antibodies were confirmed using western blot analysis. NPR-A and -C were expressed more strongly in dogs than cats. In both species, these expressions were stronger in the atria than the ventricles, with stronger expression in the left ventricles than the right. NPR-B was largely very weekly or undetected. In canine and feline cardiac tissues, the expressional distribution of NPR-A, -B, and -C closely matched that of atrial natriuretic peptide, brain natriuretic peptide, and C-type natriuretic peptide as the ligands for corresponding receptors.