Long-term ischaemic preconditioning of the heart induced by repeated beta-adrenergic stress.
In the present study we tested the preconditioning effect of repeated beta adrenergic stress induced by Isoproterenol in chronically instrumented, conscious rabbits. We have found that at least 5 intravenous administrations of Isoproterenol, repeated at 10 min intervals, were necessary to induce a long-term cardiac adaptation manifested by a significant reduction of the harmful ischaemic changes due to cardiac stress 24 and 48 hours after preconditioning. These results suggest that a well-defined threshold level of the preconditioning stress is needed to trigger induction of metabolic changes leading to development of delayed and long-term cardiac adaptation.
Kovanecz
I
I
Department of Pharmacology, Albert Szent-Györgyi Medical University, Szeged, Hungary.
Papp
J G
JG
Szekeres
L
L
D000318:Adrenergic beta-Agonists / Q000008:administration & dosage / Q000494:pharmacology*; D000818:Animals; D004056:Differential Threshold; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D004562:Electrocardiography; D006321:Heart / Q000187:drug effects*; D019157:Ischemic Preconditioning, Myocardial; D007545:Isoproterenol / Q000008:administration & dosage / Q000494:pharmacology*; D008297:Male; D011817:Rabbits; D013997:Time Factors
D000318:Adrenergic beta-Agonists; D007545:Isoproterenol