title: Blockade of spinal nerves inhibits expression of neural growth factor in the myocardium at an early stage of acute myocardial infarction in rats.
abstract: BACKGROUND
  Neural growth factor (NGF) is required for healing and sprouting of cardiac sympathetic and sensory nerves and plays important roles in cardiac protection, sustaining cardiac function and regeneration in ischaemic heart disease. The overexpression or lack of the NGF could be harmful to the heart. In this study, we examined the role of spinal nerves in the modulation of expression of the NGF in the myocardium at risk of ischaemia soon after acute myocardial infarction in rats.
  
  
  METHODS
  Coronary artery occlusion (CAO) was carried out in anaesthetized rats with and without preconditioning of blockade of the spinal nerves. The expression of the NGF protein and mRNA in the myocardium at risk of ischaemia was examined using immunohistochemical assay, enzyme-linked immunosorbent assay, and real-time quantitative reverse transcription polymerase chain reaction assay.
  
  
  RESULTS
  In the left ventricle, immunoreactive cells and fibre-like structures were mainly located in the myocardium and in the epicardium. The NGF protein expression was increased by two-fold in the myocardium at risk of ischaemia during the 60 min of CAO, while the NGF mRNA was up-regulated three-fold, at 360 min after acute myocardial infarction. The blockade of the spinal nerves completely abolished the up-regulation of the NGF in the myocardium (P<0.05).
  
  
  CONCLUSIONS
  The spinal nerves innervating the heart may play an important role in sustaining the up-regulation of the NGF in the myocardium early after acute myocardial infarction, an effect which can be inhibited by the blockade of these nerves.
authors.affiliation: Department of Anesthesiology,  Shanxi Medical University and Second Hospital of Shanxi Medical University, 56 Xinjian Nan Road, Taiyuan 030001, Shanxi,  China.
authors.forename: W
authors.initials: W
authors.lastname: Yue
authors.forename: Z
authors.initials: Z
authors.lastname: Guo
mesh_terms: D000208:Acute Disease; D000818:Animals; D004562:Electrocardiography; D006439:Hemodynamics; D008297:Male; D009203:Myocardial Infarction / Q000378:metabolism*; D009206:Myocardium / Q000378:metabolism*; D020932:Nerve Growth Factor / Q000032:analysis / Q000235:genetics / Q000502:physiology*; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D017207:Rats, Sprague-Dawley; D013127:Spinal Nerves / Q000502:physiology*
chemical_list: D012333:RNA, Messenger; D020932:Nerve Growth Factor