Differential structure-activity relationships of atrial peptides as natriuretics and renal vasodilators in the dog.
Natriuretic-diuretic and vasodilator activities of synthetic atriopeptin (AP)-related peptides were examined in the anesthetized dog. We have selected, the naturally occurring, APIII as the reference compound for comparison with various related peptides. APIII is a 24 amino acid peptide with the sequence ser-ser-cys-phe-gly-gly-arg-ile-asp-arg-ile-gly-ala-gln-ser-gly-leu-gly- cys-asn-ser-phe-arg-tyr-OH. APII, another peptide isolated from atrial extracts, lacks the C-terminal arg- of APIII. N-terminal amino acid extensions on APIII or APII, exhibited enhanced natriuretic-diuretic effectiveness. Furthermore, the maximum response obtained by ser-leu-arg-arg-APIII and arg-arg-APIII were significantly higher and the dose-response curve was not parallel to that obtained with APIII. In contrast, there were no significant qualitative or quantitative differences between the renal blood flow responses produced by the N-terminal extended peptides and APII or APIII. These results suggest a heterogeneity of AP receptors in vascular and renal tubular tissues.
Katsube
N
N
Wakitani
K
K
Fok
K F
KF
Tjoeng
F S
FS
Zupec
M E
ME
Eubanks
S R
SR
Adams
S P
SP
Needleman
P
P
D000595:Amino Acid Sequence; D000818:Animals; D009320:Atrial Natriuretic Factor; D004285:Dogs; D004305:Dose-Response Relationship, Drug; D007668:Kidney / Q000098:blood supply*; D008297:Male; D009124:Muscle Proteins / Q000494:pharmacology*; D009318:Natriuresis / Q000187:drug effects*; D013329:Structure-Activity Relationship; D014664:Vasodilation / Q000187:drug effects*
D009124:Muscle Proteins; D009320:Atrial Natriuretic Factor