title: Differential effects of the calcitonin gene-related peptide on cardiac performance in acute myocardial ischemia and reperfusion in isolated rat hearts.
abstract: BACKGROUND
  The cardioprotective effects of the calcitonin gene-related peptide (CGRP) are known; however, the profiles of CGRP given pre- and postischemia as a therapeutic agent in acute myocardial ischemia and reperfusion remain elusive.
  
  
  METHODS
  The effects of CGRP on cardiac performance in isolated rat hearts subjected to 50 min global ischemia followed by 60 min reperfusion were investigated.
  
  
  RESULTS
  It was found that global ischemia and reperfusion significantly decreased left ventricular developed pressure (LVDP) and heart rate (HR) and elevated left ventricular end diastolic pressure (LVEDP). CGRP (10-7 mol/L) given before the ischemia caused significant increases in LVDP (38±9%, P<0.05) and HR (16±5%, P<0.05), compared to the control. CGRP (administered at the beginning of reperfusion) significantly reduced LVEDP and left ventricular systolic pressure (LVSP) compared to controls by 30±7% and 28±7%, respectively (P<0.05). When compared to the pre-ischemia treatment, LVEDP and LVSP were reduced by 20±7% and 26±7%, respectively (P<0.05). No significant changes in the LVDP and HR were detected when compared to the controls. The effects of CGRP could be reversed by CGRP8-37, a specific antagonist of the CGRP receptor.
  
  
  CONCLUSIONS
  The results indicated a differential effect of CGRP on cardiac performance following acute ischemia/reperfusion.
authors: Department of Anesthesiology, Shanxi Medical University and Second Hospital of Shanxi Medical University, Taiyuan, Shanxi, China.
authors: N
authors: N
authors: Liu
authors: L-Z
authors: LZ
authors: Zhang
authors: Y
authors: Y
authors: Han
authors: Z
authors: Z
authors: Guo
mesh_terms: D000818:Animals; D015740:Calcitonin Gene-Related Peptide / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D000077221:Calcitonin Gene-Related Peptide Receptor Antagonists; D004305:Dose-Response Relationship, Drug; D006321:Heart / Q000187:drug effects*; D006339:Heart Rate / Q000187:drug effects; D066298:In Vitro Techniques; D008297:Male; D015428:Myocardial Reperfusion Injury / Q000188:drug therapy* / Q000503:physiopathology; D010446:Peptide Fragments / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D016277:Ventricular Function, Left / Q000187:drug effects
chemical_list: D000077221:Calcitonin Gene-Related Peptide Receptor Antagonists; D010446:Peptide Fragments; C058636:calcitonin gene-related peptide (8-37); D015740:Calcitonin Gene-Related Peptide