TY - JOUR
T1 - Transient ischemia cannot precondition the rabbit heart against postischemic contractile dysfunction
AU - Asimakis, Gregory K.
AU - Lick, Scott D.
AU - Conti, Vincent R.
N1 - Funding Information:
Expert technical assistance was provided by Karen Inner-McBride, Matthew Smith, and Clinton Bell. We thank Glynda Ott for preparation of the manuscript. This study was funded by an intramural grant to Dr Lick and by National Institutes of Health grant RO1 HL-50466 to Dr Asimakis.
PY - 1996/8
Y1 - 1996/8
N2 - Background. The rat heart is preconditioned against postischemic contractile dysfunction by a brief period of transient ischemia before a prolonged ischemic period. However, the rabbit heart does not receive such cardioprotection from pretreatment with a single transient ischemia periods. We hypothesized that in the rabbit heart, a multiple cycle of transient ischemia is required to reach a threshold necessary to precondition against postischemic contractile dysfunction. Methods. To test this hypothesis, we subjected isolated, perfused rabbit hearts to either one 5-minute transient ischemic period or three 5-minute transient ischemic periods followed by a 40-minute period of warm ischemia and 30 minutes of reperfusion. Control hearts (no pretreatment with transient ischemia) were examined simultaneously. Left ventricular developed pressure was measured with an intraventricular balloon. Results. Postischemic recoveries (expressed as percent of preischemic values) of left ventricular developed pressure for the group with one ischemic period and the group with three ischemic periods were 43% ± 5% (n = 5) and 38% ± 6% (n = 6), respectively. These values were not significantly different from control values. Conclusions. Neither one nor three periods of transient ischemia protect the isolated, perfused rabbit heart from postischemic contractile dysfunction. Therefore, the rabbit heart may not have the capacity to be ischemically preconditioned against postischemic contractile dysfunction.
AB - Background. The rat heart is preconditioned against postischemic contractile dysfunction by a brief period of transient ischemia before a prolonged ischemic period. However, the rabbit heart does not receive such cardioprotection from pretreatment with a single transient ischemia periods. We hypothesized that in the rabbit heart, a multiple cycle of transient ischemia is required to reach a threshold necessary to precondition against postischemic contractile dysfunction. Methods. To test this hypothesis, we subjected isolated, perfused rabbit hearts to either one 5-minute transient ischemic period or three 5-minute transient ischemic periods followed by a 40-minute period of warm ischemia and 30 minutes of reperfusion. Control hearts (no pretreatment with transient ischemia) were examined simultaneously. Left ventricular developed pressure was measured with an intraventricular balloon. Results. Postischemic recoveries (expressed as percent of preischemic values) of left ventricular developed pressure for the group with one ischemic period and the group with three ischemic periods were 43% ± 5% (n = 5) and 38% ± 6% (n = 6), respectively. These values were not significantly different from control values. Conclusions. Neither one nor three periods of transient ischemia protect the isolated, perfused rabbit heart from postischemic contractile dysfunction. Therefore, the rabbit heart may not have the capacity to be ischemically preconditioned against postischemic contractile dysfunction.
UR - http://www.scopus.com/inward/record.url?scp=0030219176&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0030219176&partnerID=8YFLogxK
U2 - 10.1016/0003-4975(96)00423-7
DO - 10.1016/0003-4975(96)00423-7
M3 - Article
C2 - 8694620
AN - SCOPUS:0030219176
SN - 0003-4975
VL - 62
SP - 543
EP - 549
JO - Annals of Thoracic Surgery
JF - Annals of Thoracic Surgery
IS - 2
ER -