Effects of different peptide fragments derived from proadrenomedullin on gene expression of adrenomedullin gene.
Primary culture of vascular smooth muscle cells (VSMC) from rat aorta was used for the study of the effect of different peptides derived from proadrenomedullin on the expression of adrenomedullin (ADM) gene. ADM and preproADM(22-41) (PAMP) secreted by VSMC were measured by radioimmunoassay, and ADM mRNA in VSMC was determined by quantitative RT-PCR. After the incubation of VSMC in 10(-7)M ADM for 24h, PAMP in the medium and ADM mRNA in the VSMC were decreased by 34 and 41.3%, respectively, and cAMP concentration in the VSMC was increased by 385%. After the incubation of VSMC in 10(-7)M PAMP for 24h, ADM in the medium and ADM mRNA in the VSMC were decreased by 12.2 and 39.1%, respectively, and cAMP concentration in the VSMC was increased by 67%. The decreased ADM mRNA in VSMC induced by the ADM and PAMP treatment was completely reversed by the pre-treatment of the cells in 10(-7)M protein kinase inhibitor for 30 min. After the incubation of VSMC in 10(-7)M preproADM(153-185) (ADT) for 24h, however, ADM in the medium and ADM mRNA in the VSMC were increased by 21 and 35.2%. The increased ADM mRNA in VSMC induced by the ADT treatment was partially blocked by the co-incubation in ADM and ADT, and was totally blocked by the co-incubation in PAMP+ADM and ADT, but was not blocked by the co-incubation in PAMP and ADT. Our results suggest that the four peptides derived from proadrenomedullin may have different effects, possibly through a cAMP-dependent pathway, on the expression of ADM gene.
Institute of Cardiovascular Disease, Peking University First Hospital, 100034, Beijing, China.
Yong Fen
YF
Qi
Ding Fang
DF
Bu
Da Di
DD
Niu
Yan Rong
YR
Shi
Shu Heng
SH
Wang
Yong Zheng
YZ
Pang
Chao Shu
CS
Tang
Jun Bao
JB
Du
D053607:Adrenomedullin; D000818:Animals; D001011:Aorta / Q000378:metabolism; D002478:Cells, Cultured; D000242:Cyclic AMP / Q000378:metabolism; D009130:Muscle, Smooth / Q000166:cytology; D010446:Peptide Fragments / Q000737:chemistry* / Q000378:metabolism / Q000494:pharmacology*; D010455:Peptides / Q000737:chemistry / Q000378:metabolism*; D016133:Polymerase Chain Reaction; D011498:Protein Precursors / Q000737:chemistry* / Q000378:metabolism; D011506:Proteins / Q000737:chemistry* / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D011863:Radioimmunoassay; D051381:Rats; D017208:Rats, Wistar; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013997:Time Factors
D010446:Peptide Fragments; D010455:Peptides; D011498:Protein Precursors; D011506:Proteins; D012333:RNA, Messenger; C094997:adrenotensin; C088633:proadrenomedullin; D053607:Adrenomedullin; D000242:Cyclic AMP