Effect of human adrenomedullin on vascular resistance of the canine tibia.
An ex vivo model of a perfused canine tibia was used to investigate the effect of human adrenomedullin, a novel peptide with known vasodilator properties, on the vascular resistance of bone. Human adrenomedullin has a potent and long-lasting vasodilator effect in the canine tibia following precontraction of vascular smooth muscle by infusion of prostaglandin F2 alpha. A 0.1 ml bolus injection of 10(-5) M human adrenomedullin suppressed the pressor response of the canine tibia preparation to an infusion of norepinephrine by 43-52% for a duration of 100 minutes. An injection of 10(-6) adrenomedullin suppressed the pressor response to an infusion of norepinephrine by 22-23% for a duration of 40 minutes. These data suggest that human adrenomedullin may be a potent and long-acting vascular smooth-muscle relaxant in bone.
Kato
T
T
Department of Orthopedics, Mayo Clinic, Rochester, Minnesota 55905, USA.
Bishop
A T
AT
Wood
M B
MB
Adams
M L
ML
D000109:Acetylcholine / Q000494:pharmacology; D053607:Adrenomedullin; D000818:Animals; D004285:Dogs; D005260:Female; D006801:Humans; D066298:In Vitro Techniques; D008297:Male; D009131:Muscle, Smooth, Vascular / Q000187:drug effects; D010455:Peptides / Q000494:pharmacology*; D010477:Perfusion; D013977:Tibia / Q000098:blood supply* / Q000187:drug effects; D014655:Vascular Resistance / Q000187:drug effects*; D014665:Vasodilator Agents / Q000494:pharmacology*
D010455:Peptides; D014665:Vasodilator Agents; D053607:Adrenomedullin; D000109:Acetylcholine