[The cardioprotective effect and mechanism of lumbrokinase]

Yao Xue Xue Bao. 2006 Mar;41(3):247-51.
[Article in Chinese]


Aim: To investigate the protective effect of lumbrokinase against myocardial ischemia and to further explore its underlying mechanisms.

Methods: The effect of lumbrokinase on myocardial ischemia was observed by a model of acute myocardial infarction due to permanent ligation of the left anterior descending coronary artery in rats. Patch-clamp technique and laser scanning confocal microscopy were utilized to study the action of lumbrokinase on L-type calcium current (ICa-L) and intracellular calcium concentration ([Ca2+]i).

Results: Lumbrokinase decreased the infarct size of myocardium in a dose-dependent manner. The inhibitory rate of lumbrokinase at the dose of 20, 40 and 80 mg x kg(-1) was 7.7%, 34.6% and 46.2%, respectively. The electrophysiological studies displayed that, at + 10 mV, the ICa-L was markedly reduced from (-14.42 +/- 1.53) pA/pF to (-11.33 +/- 1.40) pA/pF (decreased by 21.4%, P <0.01) and (-9.92 +/- 1.31) pA/pF (decreased by 36.5%, P <0.01) by lumbrokinase (10 and 50 micromol x L(-1)), respectively. Confocal experiments showed that 10 micromol x L(-1) lumbrokinase showed no obvious effects on [Ca2+]i at resting states (P > 0.05). However, the increase of [Ca2+]i induced by 60 mmol x L(-1) KCl was distinctly limited by 10 micromol x L(-1) lumbrokinase (P <0.01). Within 240 s, the no obvious peak value of fluorescent intensity (FI) was shown.

Conclusion: Lumbrokinase showed protective action against myocardial infarction in rats. The possible mechanisms of anti-ischemia could be attributed to decreasing ICa-L and [Ca2+] of ventricular myocytes in rats.

Publication types

  • English Abstract
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Calcium / metabolism
  • Calcium Channels, L-Type / metabolism
  • Cardiotonic Agents / pharmacology*
  • Endopeptidases / pharmacology*
  • Female
  • Heart Ventricles
  • Male
  • Myocardial Infarction / metabolism*
  • Myocardial Infarction / pathology
  • Myocardium / pathology
  • Myocytes, Cardiac / metabolism
  • Rats
  • Rats, Wistar


  • Calcium Channels, L-Type
  • Cardiotonic Agents
  • Endopeptidases
  • lumbrokinase
  • Calcium