Angiotensin, vasopressin, and atrial natriuretic peptide in the rat eye.

Angiotensin (Ang), vasopressin (VP) and atrial natriuretic peptide (ANP) were assayed in the anterior uvea and retina from eyes of decapitated rats and rats perfused through the heart with phosphate buffered saline to remove peptides from blood and ocular fluids. All peptides were detected, and ANP was the most abundant. Uveal content of each peptide was greater than the retina. Perfusion did not affect ANP or VP content, but Ang was eliminated. Washout may explain the lack of immunohistochemical localization in the eye for Ang, but not VP. Also, washout does not account for available immunohistochemical data describing the localization of ANP in ocular tissue.