In:
Acta Physiologica Scandinavica, Wiley, Vol. 149, No. 1 ( 1993-09), p. 77-83
Abstract:
The renal effects of urodilatin and atrial natriuretic peptide (ANP) were examined in conscious dogs during acute volume expansion maintained through independent infusions of water and NaCl. Peptide was infused in a step‐up fashion, in 40‐min periods at rates of 2.5, 12.5 and 50.0 ng kg ‐1 min ‐1 (ANP, urodilatin) or 0.5, 2.5 and 10.0 ng kg ‐1 min ‐1 (second series of urodilatin). ANP immunoreactivity (ANPir) in plasma was measured with an antibody showing 100% cross‐reactivity with urodilatin. At 50 ng kg ‐1 min ‐1 , ANP increased plasma ANPir some 10‐fold (64 ± 6 pg ml ‐ 1 to 728 ± 82 pg ml ‐1 ) while urodilatin elicited a 25‐fold increase in ANPir (78± 13 pg ml ‐1 to 1645 ± 204 pg ml ‐1 ). ANP doubled sodium excretion (61 ± 12 to 124±30 μmol min ‐1 , P 〈 0.05) while urodilatin increased sodium excretion to 269 ± 45 μmol min ‐1 . Both peptides approximately doubled urine flow. Urodilatin at 10 ng kg ‐1 min ‐1 increased sodium excretion from 57±17μmol min ‐1 to 106 ± 25 μmol min ‐1 , i.e. similar to the response ANP elicited at 50 ng kg ‐1 min ‐1 . In the time control series a significant fall in sodium excretion was observed, despite the continuous replacement of sodium and water. The results demonstrate that in identical, relatively high doses, the changes in sodium excretion, diuresis, heart rate (HR) and arterial pressures elicited by urodilatin are more pronounced than those of ANP. However, such amounts seem to produce plasma concentrations of urodilatin higher than those of ANP. A given small increase in sodium excretion required higher plasma levels of ANP compared to urodilatin. Therefore, for a given modest plasma level, urodilatin is a more potent natriuretic agent than ANP.
Type of Medium:
Online Resource
ISSN:
0001-6772
,
1365-201X
DOI:
10.1111/apha.1993.149.issue-1
DOI:
10.1111/j.1748-1716.1993.tb09594.x
Language:
English
Publisher:
Wiley
Publication Date:
1993
detail.hit.zdb_id:
2012166-0
detail.hit.zdb_id:
101-6
SSG:
12
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