[Immunohistochemical observation of ANP in rhesus monkey heart and lung]

Rabbit anti-human atriopeptin serum and the peroxidase anti-peroxidase (PAP) immunohistochemical technique were used to study atrial natriuretic polypeptide (ANP) in the heart and lung of rhesus monkeys. ANP-like active substance was found in atrial myocardium cells and in bronchial epithelial cells as well as in some cells of the alveolar septum. The substance appeared as brown particulates mainly located in the cytoplasm around the nucleus, mostly at opposite poles of the nucleus. The nature of these particulates will be determined.