Effect of Metabolic Inhibitors and Ischaemia on Contractile Force and Magnesium Efflux in the Isolated Perfused Rat Heart

  • B. I. Hustler
  • J. J. Waring
  • J. Singh
Chapter

Summary

This study investigates the effects of ischaemia using reduced flow rate and metabolic inhibition by rotenone, KCN, oligomycin and DNP on contractile force and net Mg2+ efflux from the isolated perfused rat-heart. There was a significant (Student’s t-test; P < 0.01) decrease in force of contraction and coronary pressure during 10 min of ischaemic conditions and this was accompanied by a significant (P < 0.001) increase in Mg2+ efflux. Perfusion of the heart for 10 min with Mg2+-free KH containing metabolic inhibitors either 10-5M rotenone, 10-7M KCN. or 10-7 Oligomycin B resulted in a decrease in contractile force and a small but not significant (P > 0.01)increase in net Mg2+ efflux. In contrast, perfusion with DNP, an oxidative phosphorylation uncoupler, resulted in a significant decrease in contractile force accompanied by a highly significant (increase in Mg2+ efflux. The results indicate that both ischaemia and loss of the mitochondrial proton gradient are associated with Mg2+ efflux, and a concomitant decrease in contractile force in the isolated heart.

Keywords

Contractile Force Metabolic Inhibitor Effluent Sample Coronary Pressure Perfusion Flow Rate 
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References

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Copyright information

© Kluwer Academic Publishers 1997

Authors and Affiliations

  • B. I. Hustler
    • 1
  • J. J. Waring
    • 1
  • J. Singh
    • 1
  1. 1.Department of Applied BiologyUniversity of Central LancashirePreston, LancashireUK

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