1. Metabolic and functional effects of two protocols of preconditioning were compared in @entity35 isolated hearts subjected to 20 min global ischaemia (37 degrees C) and reperfusion (30 min Langendorff + 15 min working). Prior to the ischaemic period, hearts were perfused according to Langendorff (control group) or were preconditioned by three 5 min cycles or two 10 min cycles of ischaemia and reperfusion (PC-I and PC-II groups, respectively). 2. There was no difference in the contractile function between the two preconditioned groups at the onset of sustained ischaemia, although the PC-II group showed enhanced release of @entity859 ( @entity7308 ), @entity14572 , @entity3625 and @entity3624 into the interstitium accompanied by losses of tissue @entity3211 (sigmaAN = @entity855 + @entity857 + @entity860 ), total @entity908 (sigmaCr = @entity1734 + @entity908 ) and activation of glycolysis following the preconditioning period. During reperfusion, the PC-I group showed enhanced functional recovery, higher contents of sigmaAN and sigmaCr, and the smallest @entity880 dehydrogenase release compared with these indices in the control and PC-II groups. Postischaemic @entity296 was similar in the control and PC-II groups. 3. Functional recovery of hearts in both preconditioned groups was positively correlated with myocardial contents of @entity855 , sigmaAN and sigmaCr at the end of reperfusion, but not with pre-ischaemic Ado release into the interstitium. The results suggest that pre-ischaemic disturbances of energy metabolism, rather than activation of Ado receptors or stunning, may contribute to efficacy of multiple preconditioning in the @entity35 isolated heart.

Association of pre-ischaemic disturbances in energy metabolism with postischaemic dysfunction of the XXXX isolated working heart.

@entity1734 :: ('CHEBI:17287', 'Chemical') :: ['phosphocreatine'] @entity296 :: ('MESH:D009202', 'Disease') :: ['myocardial dysfunction'] @entity859 :: ('MESH:D000241', 'Chemical') :: ['adenosine'] @entity7308 :: ('MESH:C110027', 'Chemical') :: ['Ado'] @entity3625 :: ('MESH:D019271', 'Chemical') :: ['hypoxanthine'] @entity3624 :: ('MESH:D019820', 'Chemical') :: ['xanthine'] @entity908 :: ('MESH:D003401', 'Chemical') :: ['creatine'] @entity14572 :: ('MESH:D007288', 'Chemical') :: ['inosine'] @entity855 :: ('MESH:D000255', 'Chemical') :: ['ATP'] @entity880 :: ('MESH:D019344', 'Chemical') :: ['lactate'] @entity35 :: ('10116', 'Species') :: ['rat'] @entity860 :: ('MESH:D000249', 'Chemical') :: ['AMP'] @entity857 :: ('MESH:D000244', 'Chemical') :: ['ADP'] @entity3211 :: ('MESH:D000227', 'Chemical') :: ['adenine nucleotides']
@entity35 :: (10116,Species) :: ['rat']
