[Changes in adrenomedullin and receptor activity-modifying protein 2 mRNA in myocardium and vessels during L-NNA-induced hypertension in rats].
To explore the changes in adrenomedullin (ADM) and receptor activity-modifying protein 2 (RAMP2) mRNA in myocardium and vessels in hypertension, a hypertensive rat model was prepared by administering L-NNA. Contents of ADM in plasma, myocardium and vessels were measured by radioimmunoassay (RIA). The levels of pro-ADM mRNA of myocardium and vessels were determined by competitive quantitative RT-PCR. The results showed that L-NNA induced hypertension and cardiomegaly. The ratio of heart to body weight increased by 35.5% (P<0.01). In hypertensive rats the ir-ADM in plasma, myocardium and vessels was increased by 80%, 72% and 57% (P<0.01), respectively compared with the control. The amounts of ADM mRNA in myocardium and vessels were increased by 50% and 109.2% (P<0.05), respectively, and the amounts of RAMP2 mRNA was increased by 132% and 87% (P<0.01), respectively, compared with control. The levels of ADM in myocardium and vessels were positively correlated with RAMP2 mRNA, the correlation coefficients were 0.741 and 0.885 (P<0.01), respectively. The results obtained indicate that in hypertensive rats, ADM is elevated in plasma, myocardium and ves-myocardium and vessel, and ADM and RAMP2 mRNA are up-regulated in myocardium and vessel. The ADM/RAMP2 system may play an important role in the pathogenesis of hypertension.
Institute of Cardiovascular Research, the First Hospital, Peking University, Beijing 100034.
Yong-Fen
YF
Qi
Yan-Rong
YR
Shi
Ding-Fang
DF
Bu
Hong-Feng
HF
Jiang
Lin
L
Gao
Yong-Zheng
YZ
Pang
Chao-Shu
CS
Tang
D053607:Adrenomedullin / Q000378:metabolism*; D000818:Animals; D006332:Cardiomegaly / Q000139:chemically induced / Q000378:metabolism; D006973:Hypertension / Q000139:chemically induced / Q000378:metabolism*; D009206:Myocardium / Q000378:metabolism*; D019335:Nitroarginine / Q000494:pharmacology; D012333:RNA, Messenger; D051381:Rats; D058263:Receptor Activity-Modifying Protein 2 / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015854:Up-Regulation
D012333:RNA, Messenger; C545509:Ramp2 protein, rat; D058263:Receptor Activity-Modifying Protein 2; D053607:Adrenomedullin; D019335:Nitroarginine