Receptor binding affinity and thermolysin degradation of truncated and retro-inverso-isomeric ANF analogs.
The peptides H-Phe-Gly-Gly-Arg-Ile-Asp-Arg-Ile-NH2 (rANF8-15-NH2), Ac-Phe-Gly-Gly-Arg-Ile-Asp-Arg-Ile-NH2 (Ac-rANF8-15-NH2), and their corresponding retro-inverso-isomeric peptides H-D-Ile-D-Arg-D-Asp-D-Ile-D-Arg-Gly-Gly-D-Phe-NH2 (D-rANF15-8-NH2), Ac-D-Ile-D-Arg-D-Asp-D-Ile-D-Arg-Gly-Gly-D-Phe-NH2 (Ac-D-rANF15-8-NH2), were evaluated for their ability to compete for the binding of 125I-rANF5-28 to cultured spontaneously hypertensive rat (SHR) aortic smooth muscle cell membranes. Their stability toward hydrolysis by the neutral endopeptidase thermolysin was also studied. The octapeptides rANF8-15-NH2 and Ac-rANF8-15-NH2 bound with IC50's of 367 pM and 1900 pM, respectively, but were rapidly hydrolyzed by thermolysin. Retro-inverso-isomers were prepared to provide molecules with an improved enzymatic stability. The retro-inverso-isomers were completely stable to thermolysin but were virtually inactive in the binding assay (IC50 greater than 1 microM).
Berman
J M
JM
Merrell Dow Research Institute, Cincinnati, OH 45215.
Hassman
C F
CF
Buck
S H
SH
Chen
T M
TM
D000818:Animals; D001011:Aorta / Q000378:metabolism; D009320:Atrial Natriuretic Factor / Q000138:chemical synthesis / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism; D002478:Cells, Cultured; D007536:Isomerism; D007700:Kinetics; D009131:Muscle, Smooth, Vascular / Q000378:metabolism; D051381:Rats; D011918:Rats, Inbred SHR; D017461:Receptors, Atrial Natriuretic Factor; D011956:Receptors, Cell Surface / Q000378:metabolism*; D013329:Structure-Activity Relationship; D013820:Thermolysin / Q000378:metabolism*
D011956:Receptors, Cell Surface; D009320:Atrial Natriuretic Factor; D013820:Thermolysin; D017461:Receptors, Atrial Natriuretic Factor