[[File:BNP_pathwayInfluenzastructure.png|thumb|400px|The biosynthesis of proBNP and its derivatives.<ref name="Arti1">Cardiac biomarker testing in the clinical laboratory: Where do we stand? General overview of the methodology with special emphasis on natriuretic peptides, Aldo Clerico, Claudio Passino, Maria Franzini, Michele Emdin, June 2014, Clinica Chimica Acta, http://dx.doi.org/10.1016/j.cca.2014.06.003</ref>]]