LIGHT- AND ELECTRON-MICROSCOPIC INVESTIGATION OF ANP-LIKE IMMUNOREACTIVITY IN AORTA, CAROTID ARTERY AND CULTURED CARDIAC MYOCYTES OF THE RAT

In the present investigation we have sought for atrial natriuretic peptide (ANP) -like immunoreactivity in aorta, carotid artery, cultured aortic cells and cultured cardiac myocytes of the rat at the light- and electron-microscopic level using antibodies directed against atriopeptin II (5-27) . Aortic and carotid aretery sections as well as cultured aortic cells did not show any ANP-specific immunoreactivity, preabsorbable by atriopeptin II or a-rat ANP (1-28) . Cultured cardiac myocytes could be shown to contain ANP granules and secrete immunoreactive ANP.