title: [Alterations of proadrenomedullin N-terminal 20-peptide in rats with pulmonary hypertension induced by high pulmonary blood flow].
abstract: OBJECTIVE
  The mechanism of high pulmonary blood flow-induced pulmonary hypertension remains unclear. The aim of this study was to explore the effect of proadrenomedullin N-terminal 20-peptide (PAMP) on pulmonary hypertension, through examining the alterations of pulmonary PAMP expression and plasma PAMP concentration in rats with pulmonary hypertension induced by high pulmonary blood flow.
  
  
  METHODS
  Sixteen male Sprague-Dawley rats were randomly divided into control (n=8) and shunt groups (n=8). Aortocaval shunting was produced in the shunt group. After 11 weeks of shunting, systolic pulmonary artery pressure (sPAP), diastolic pulmonary artery pressure (dPAP) and mean pulmonary artery pressure (mPAP) were evaluated by using a right cardiac catheterization procedure. The ultrastructural changes in intra-acinar pulmonary arteries were observed. The concentration of plasma PAMP was measured by radioimmunoassay. The expression of PAMP in pulmonary arteries was detected by immunohistochemical assay.
  
  
  RESULTS
  sPAP, dPAP and mPAP were significantly increased in shunt rats compared with controls (P < 0.01). Ultrastructural changes, such as hyperplasia and swelling of endothelial cells, irregularity of internal elastic laminar, and hypertrophy and increased number of synthetic phenotype of smooth muscle cells, were found in intra-acinar pulmonary muscularized arteries in the shunt group. Plasma PAMP concentration (616 +/- 195 pg /mL vs 427 +/- 90 pg /mL) and PAMP expression in endothelial cells (0.62 +/- 0.09 vs 0.38 +/- 0.12) and in smooth muscle cells (0.24 +/- 0.07 vs 0.14 +/- 0.05) of pulmonary arteries increased significantly in the shut group compared with controls.
  
  
  CONCLUSIONS
  The up-regulation of pulmonary and plasm PAMP expression might be involved in the development of high pulmonary blood flow-induced pulmonary hypertension.
authors: Department of Pediatrics, Peking University First Hospital, Beijing, China. qijianguang@sohu.com
authors: Jian-Guang
authors: JG
authors: Qi
authors: Xiao-Hui
authors: XH
authors: Li
authors: Ya-Guang
authors: YG
authors: Ding
authors: Chao-Shu
authors: CS
authors: Tang
authors: Jun-Bao
authors: JB
authors: Du
mesh_terms: D053607:Adrenomedullin / Q000097:blood* / Q000235:genetics; D000818:Animals; D006976:Hypertension, Pulmonary / Q000097:blood* / Q000209:etiology / Q000473:pathology; D008297:Male; D011651:Pulmonary Artery / Q000648:ultrastructure; D011652:Pulmonary Circulation; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D053607:Adrenomedullin