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 heart in a similar fashion as ANP.
|Number of pages||9|
|Journal||Biochemical and Biophysical Research Communications|
|Publication status||Published - 1989 Jan 31|
ASJC Scopus subject areas
- Molecular Biology
- Cell Biology