IT IS A NEW DRUG CLASS, HUMAN B-TYPE NATRIURETIC PEPTIDE (HBNP), AND IS MANUFACTURED FROM E. COLI USING RECOMBINANT DNA TECHNOLOGY. IT HAS THE SAME 32 AMINO ACID SEQUENCE AS THE ENDOGENOUS PEPTIDE, WHICH IS PRODUCED BY THE VENTRICULAR MYOCARDIUM.
HUMAN BNP BINDS TO THE PARTICULATE GUANYLATE CYCLASE RECEPTOR OF VASCULAR SMOOTH MUSCLE AND ENDOTHELIAL CELLS, LEADING TO INCREASED INTRACELLULAR CONCENTRATIONS OF GUANOSINE 3'5'-CYCLIC MONOPHOSPHATE (CGMP) AND SMOOTH MUSCLE CELL RELAXATION. CYCLIC GMP SERVES AS A SECOND MESSENGER TO DILATE VEINS AND ARTERIES. NESIRITIDE HAS BEEN SHOWN TO RELAX ISOLATED HUMAN ARTERIAL AND VENOUS TISSUE PREPARATIONS THAT WERE PRECONTRACTED WITH EITHER ENDOTHELIN-1 OR THE ALPHA-ADRENERGIC AGONIST, PHENYLEPHRINE. IN HUMAN STUDIES, NESIRITIDE PRODUCED DOSE-DEPENDENT REDUCTIONS IN PULMONARY CAPILLARY WEDGE PRESSURE (PCWP) AND SYSTEMIC ARTERIAL PRESSURE IN PATIENTS WITH HEART FAILURE.