[A study on hypotensive mechanism of adrenomedullin (13-52)].
In the present study the hypotensive mechanism of AdM (13-52) was investigated in rats, both in vitro and in vivo. It was found that the hypotensive effect of AdM (13-52) could be partially inhibited by L-NG-nitro-arginine (LNNA), an inhibitor of nitric oxide synthase. The vasodilator effect of AdM (13-52) was dependent on vascular endothelium and inhibited by LNNA in a dose-dependent manner. This LNNA induced inhibitory effect could be reversed with L-Arginine. In addition, the vasodilator effect of AdM (13-52) disappeared with methylene blue (MB), which blocked cGMP formation. Using radioimmunoassay it was shown that LNNA lowered, but AdM (13-52) elevated the vascular cGMP content, while vascular cGMP content was not altered by co-application of AdM (13-52) and LNNA. The above results suggest that the vasodilator effect of AdM (13-52) might be mediated by nitric oxide.
Zhao
D
D
Institute of Cardiovascular Research, Beijing Medical University.
Tian
Q
Q
Zhao
Y T
YT
Gong
C N
CN
Han
Q D
QD
Zhang
Z K
ZK
Tang
J
J
D053607:Adrenomedullin; D000818:Animals; D000959:Antihypertensive Agents / Q000494:pharmacology*; D001013:Aorta, Thoracic / Q000378:metabolism; D001120:Arginine / Q000031:analogs & derivatives / Q000494:pharmacology; D001794:Blood Pressure / Q000187:drug effects*; D006152:Cyclic GMP / Q000378:metabolism; D066298:In Vitro Techniques; D008297:Male; D009126:Muscle Relaxation / Q000187:drug effects*; D009131:Muscle, Smooth, Vascular / Q000187:drug effects*; D019335:Nitroarginine; D010455:Peptides / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar
D000959:Antihypertensive Agents; D010455:Peptides; D053607:Adrenomedullin; D019335:Nitroarginine; D001120:Arginine; D006152:Cyclic GMP