With regard to an anti-RAMP2 antibody having a cAMP inhibitory effect and an HUVEC antiproliferative effect, the present invention provides an angiogenesis inhibitor containing said antibody as an active ingredient. Specifically, the present invention relates to, in an in vitro proliferation test: an antibody against a receptor activity modifying protein2 (RAMP2) having an antiproliferative effect of vascular endothelial cells, or immunoreactive fragments thereof； or an antibody having an effect of inhibiting cAMP production caused by animal cells through the addition of adrenomedullin, or immunoreactive fragments thereof.
