title: Brain natriuretic peptide is a novel cardiac hormone.
abstract: Using a radioimmunoassay for brain natriuretic peptide (BNP), we have measured levels of BNP-like immunoreactivity (-LI) in extract of the porcine heart, in perfusate from the isolated porcine heart and in porcine plasma. BNP-LI was detected in the extract of the atrium, though no detectable amount of BNP-LI (more than 1 ng/g) was present in the ventricle. The BNP-LI level in the porcine atrium was 148.7 +/- 23.3 ng/g. BNP-LI was also detected in the perfusate from the heart. Basal secretory rate of BNP was 3.18 +/- 0.76 ng/min. Moreover, BNP-LI was detected in porcine plasma at the concentration of 4.2 +/- 1.3 pg/ml. Gel filtration studies showed that BNP is present in the atrium as a large molecule and is secreted into the circulation as a small molecule. The percentage of BNP-LI to atrial natriuretic peptide (ANP)-LI was almost the same among the extract, the perfusate and the plasma (2-3 percent). These results indicate that BNP is synthesized in and is secreted into the circulation from the heat in a similar fashion as ANP.
authors.affiliation: Department of Medicine, Kyoto University School of Medicine, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Saito
authors.forename: K
authors.initials: K
authors.lastname: Nakao
authors.forename: H
authors.initials: H
authors.lastname: Itoh
authors.forename: T
authors.initials: T
authors.lastname: Yamada
authors.forename: M
authors.initials: M
authors.lastname: Mukoyama
authors.forename: H
authors.initials: H
authors.lastname: Arai
authors.forename: K
authors.initials: K
authors.lastname: Hosoda
authors.forename: G
authors.initials: G
authors.lastname: Shirakami
authors.forename: S
authors.initials: S
authors.lastname: Suga
authors.forename: N
authors.initials: N
authors.lastname: Minamino
mesh_terms: D000818:Animals; D016275:Atrial Function; D009320:Atrial Natriuretic Factor / Q000032:analysis; D006321:Heart / Q000502:physiology*; D020097:Natriuretic Peptide, Brain; D009419:Nerve Tissue Proteins / Q000502:physiology*; D011863:Radioimmunoassay; D013552:Swine
chemical_list: D009419:Nerve Tissue Proteins; D020097:Natriuretic Peptide, Brain; D009320:Atrial Natriuretic Factor