Changes of adrenomedullin and receptor activity modifying protein 2 (RAMP2) in myocardium and aorta in rats with isoproterenol-induced myocardial ischemia.
Adrenomedullin is a potent vasodilator peptide originally isolated from a pheochromocytoma. Recently, a novel adrenomedullin receptor has been identified as a complex of calcitonin receptor-like receptor (CRLR) and receptor activity modifying protein 2 (RAMP2). To explore the pathophysiological roles of adrenomedullin and its receptor component RAMP2 in ischemic cardiovascular diseases, we studied the changes of adrenomedullin and RAMP2 mRNA in myocardium and aorta in rats with isoproterenol (ISO)-induced myocardial impairment. In ISO-treated rats, heart became enlarged markedly, the ratio of heart to body weight was increased by 54% (P<0.01), and myocardial malondialdehyde content and plasma lactate dehydrogenase activity was elevated by 43% (P<0.01) and 138% (P<0.01), respectively. Immunoreactive adrenomedullin (ADM) in plasma, myocardium and aorta was augmented by 116.7% (P<0.01), 50.8% (P<0.01) and 12.5% (P>0.05), respectively. ADM mRNA in myocardium and aorta was increased by 96.8% (P<0.01) and 38.5% (P<0.01), respectively. RAMP2 mRNA in myocardium and aorta was increased by 19.6% (P<0.05) and 15.8% (P<0.01), respectively. These results suggest that the increase of ADM level and the up-regulation of ADM and RAMP2 gene in myocardium and aorta may be significant in the pathogenesis of ischemic myocardiopathy.
Institute of Cardiovascular Disease, Peking University First Hospital, Beijing 100034, China.
Yong Fen
YF
Qi
Yan Rong
YR
Shi
Ding Fang
DF
Bu
Yong Zheng
YZ
Pang
Chao Shu
CS
Tang
D053607:Adrenomedullin; D000818:Animals; D001011:Aorta / Q000187:drug effects / Q000378:metabolism*; D004195:Disease Models, Animal; D006321:Heart / Q000187:drug effects / Q000503:physiopathology; D047908:Intracellular Signaling Peptides and Proteins; D007545:Isoproterenol / Q000494:pharmacology*; D008297:Male; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D017202:Myocardial Ischemia / Q000139:chemically induced* / Q000378:metabolism* / Q000473:pathology; D009206:Myocardium / Q000378:metabolism* / Q000473:pathology; D010455:Peptides / Q000097:blood / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D058261:Receptor Activity-Modifying Proteins
D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins; D010455:Peptides; D012333:RNA, Messenger; D058261:Receptor Activity-Modifying Proteins; D053607:Adrenomedullin; D007545:Isoproterenol