title: Calcitonin gene-related peptide in aerobic exercise induces collateral circulation development in rat ischemia myocardium.
abstract: OBJECTIVE
  Aerobic exercise may offer favorable effects for coronary perfusion in the myocardial ischemia area, although the underlying molecular mechanisms remain unclear. This study was designed to investigate the effect of aerobic exercise on the collateral circulation in the ischemia myocardium and to evaluate calcitonin gene-related peptide (CGRP) changes during this process.
  
  
  RESULTS
  Wistar rats were randomly divided into 3 groups of 7 rats each: a sham operated group (Sham), a myocardial ischemia-only group (MI) and a MI plus aerobic exercise group (MI+AE). The rat myocardial ischemia model was established by injecting isoprenaline (2mg/kg, i.p.). The aerobic exercise training consisted of swimming (40min/d, 5d/wk) for 4 weeks. At the end-points, after echocardiographic analysis was performed, blood and ischemia myocardium samples were collected and analyzed by ELISA to quantify the CGRP protein. The dorsal root ganglia were isolated and analyzed by reverse transcription polymerase chain reaction (RT-PCR) to examine the CGRP mRNA expression, and ischemia myocardium capillary density was evaluated by immunohistochemistry. Our data showed that the capillary density in the left ventricle and heart function were significantly decreased with decreased CGRP production in the MI rats, which were reversed by aerobic exercise in the MI+AE rats.
  
  
  CONCLUSIONS
  These results indicate that aerobic exercise may alleviate myocardial ischemia through collateral circulation development with increased CGRP production. CGRP may play an important role in developing the collateral circulation.
authors.affiliation: Department of Rehabilitation Medicine, The Affiliated Hospital of Qingdao University, Qingdao 266003, Shandong, China; Clinical Medical School, Jining Medical University, Jining 272013, Shandong, China.
authors.forename: YuanHui
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Clinical Medical School, Jining Medical University, Jining 272013, Shandong, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Clinical Medical School, Jining Medical University, Jining 272013, Shandong, China.
authors.forename: Li
authors.initials: L
authors.lastname: Jia
authors.affiliation: Clinical Medical School, Jining Medical University, Jining 272013, Shandong, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Liu
authors.affiliation: Clinical Medical School, Jining Medical University, Jining 272013, Shandong, China.
authors.forename: Kun
authors.initials: K
authors.lastname: Liu
authors.affiliation: Clinical Medical School, Jining Medical University, Jining 272013, Shandong, China.
authors.forename: QiZhen
authors.initials: Q
authors.lastname: Feng
authors.affiliation: Department of Rehabilitation Medicine, The Affiliated Hospital of Qingdao University, Qingdao 266003, Shandong, China. Electronic address: sakulawangqiang@hotmail.com.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Wang
mesh_terms: D000818:Animals; D015740:Calcitonin Gene-Related Peptide / Q000097:blood / Q000235:genetics / Q000378:metabolism*; D002196:Capillaries / Q000473:pathology / Q000503:physiopathology; D003097:Collateral Circulation; D006334:Heart Function Tests; D006352:Heart Ventricles / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology; D008297:Male; D023421:Models, Animal; D017202:Myocardial Ischemia / Q000097:blood / Q000235:genetics / Q000378:metabolism* / Q000503:physiopathology*; D010805:Physical Conditioning, Animal; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D017208:Rats, Wistar; D013318:Stroke Volume
chemical_list: D012333:RNA, Messenger; D015740:Calcitonin Gene-Related Peptide
keywords: Aerobic exercise; CGRP; Collateral circulation; Myocardial ischemia