title: [Precondition with doxycycline administration abates ischemia/reperfusion injury and reduces the expression of matrix metalloproteinase-1/9 in myocardium in rat in vivo].
abstract: OBJECTIVE
  To investigate the effects of preconditioning with doxycycline on ischemia/reperfusion (I/R) injury and expressions of matrix metalloproteinase-1 (MMP-1) and MMP-9 in myocardium in rat in vivo.
  
  
  METHODS
  Sixty-four healthy male SD rats, weighing 300-350 g, were randomly divided into three groups: sham operation group (n = 16), I/R group (n = 24), and doxycycline preconditioning group (n = 24). The heart function, plasma level of creatine kinase (CK) and lactate dehydrogenase (LDH), and the activity of myeloperoxidase (MPO) were respectively determined in rat myocardium after ischemia for 60 minutes and reperfusion for 120 minutes or with the same procedure but with precondition of Doxycycline. Also the expressions of MMP-1 and MMP-9 was determined by immunohistochemistry.
  
  
  RESULTS
  In I/R group, left ventricular systolic pressure (LVSP) and the maximum and minimum first derivative of LVSP (+/-dp/dtmax) were significantly less, and left ventricular end diastolic pressure (LVEDP), CK, LDH, the activity of MPO, and the protein expressions of MMP-1 and MMP-9 were remarkably higher compared with the sham operation group (P<0.05 or P<0.01). Heart function was improved, CK, LDH, MPO and the expressions of MMP-1 and MMP-9 were reduced obviously by doxycycline preconditioning compared with the I/R group (P<0.05 or P<0.01).
  
  
  CONCLUSIONS
  Precondition with doxycycline could remarkably abate I/R injury of rat myocardium in vivo and inhibit the expressions of MMP-1 and MMP-9.
authors.affiliation: Department of Cardiology, The Union Hospital, Fujian Medcial University, Fujian Institute of Senile Disease, Fuzhou 350001, Fujian, China.
authors.forename: Li-ming
authors.initials: LM
authors.lastname: Wu
authors.forename: Lin
authors.initials: L
authors.lastname: Fan
authors.forename: Liang-long
authors.initials: LL
authors.lastname: Chen
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D004318:Doxycycline / Q000494:pharmacology* / Q000627:therapeutic use; D019157:Ischemic Preconditioning, Myocardial; D008297:Male; D020781:Matrix Metalloproteinase 1 / Q000378:metabolism*; D020780:Matrix Metalloproteinase 9 / Q000378:metabolism*; D015428:Myocardial Reperfusion Injury / Q000378:metabolism / Q000517:prevention & control*; D009206:Myocardium / Q000378:metabolism*; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D020780:Matrix Metalloproteinase 9; D020781:Matrix Metalloproteinase 1; D004318:Doxycycline