natriuretic peptide family
ANP: atrial natriuretic peptide
http://en.wikipedia.org/wiki/Atrial_natriuretic_peptide
BNP: brain natriureti peptide
http://en.wikipedia.org/wiki/Brain_natriuretic_peptide
CNP: c-type natriuretic peptide
http://en.wikipedia.org/wiki/C-type_Natriuretic_Peptide
UNP: urodilatin
http://en.wikipedia.org/wiki/Urodilatin