[Effects of 11,12-epoxyeicosatrienoic acid on cardioplegia and reperfusion arrhythmias in the isolated immature rabbit hearts].
OBJECTIVE
The aim of the present study was to study the Effects of 11,12-epoxyeicosatrienoic acid (11,12-EET) on cardioplegia and reperfusion arrhythmias in the isolated perfused immature rabbit hearts.


METHODS
Isolated immature rabbit hearts were randomly divided into two groups: group 1 (St. Thomas No.2 solution control n = 8) and group 2 (St. Thomas No.2 solution plus 11,12-EET n = 8). By means of Langendorff technique, these isolated rabbit hearts underwent (15 degrees C) hypothermia, 2 hours of ischemia after infusion of cardioplegic solution and 1 hour of reperfusion (37 degrees C). The mean times until the cessation of both electrical and mechanical activity were measured after infusion of cardioplegia. The same index until occurrence of both electrical and mechanical activity after reperfusion was observed too. We also measured the arrhythmias score, heart rate, coronary blood flow during the reperfusion and the myocardial water content, myocardial calcium content at the endpoint of the reperfusion period.


RESULTS
The times until electrical [(9.3 +/- 0.9) s vs (13.6 +/- 1.9) s, P < 0.01] and mechanical [(4.5 +/- 1.7) vs (7.3 +/- 2.1) s, P < 0.05] activity arrest were significantly shorter in the group 2 than those in the control group. 11,12-EET also provided significantly better myocardial water content [(84 +/- 4)% vs (90 +/- 5)%, P < 0.01], arrhythmia scores (2.03 +/- 0.83 vs 3.88 +/- 1.25, P < 0.01), coronary blood flow and myocardial calcium content [(3.22 +/- 0.33) micro mol/gram dry weight (gdw) vs (3.97 +/- 0.26) micro mol/gdw, P < 0.01] compared with control. There were no significant changes with heart rate and the mean times until occurrence of both electrical and mechanical activity after reperfusion.


CONCLUSIONS
These data suggest that 11,12-EET added to the cardioplegic solution of St. Thomas No.2 has better cardioplegia effects and lower incidence of reperfusion arrhythmias.
Zhou
Ming-yang
MY
Department of Surgery, Cardiovascular Institute and Fu Wai Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing 100037, China.
Wu
Qing-yu
QY
Zhong
Xing
X
Long
Cun
C
Wen
Fu-xing
FX
Qin
Xiao-yan
XY
D015126:8,11,14-Eicosatrienoic Acid / Q000031:analogs & derivatives* / Q000494:pharmacology*; D000818:Animals; D001145:Arrhythmias, Cardiac / Q000517:prevention & control*; D006324:Heart Arrest, Induced; D006339:Heart Rate / Q000187:drug effects; D066298:In Vitro Techniques; D015428:Myocardial Reperfusion Injury / Q000517:prevention & control*; D011817:Rabbits
C046783:11,12-epoxy-5,8,14-eicosatrienoic acid; D015126:8,11,14-Eicosatrienoic Acid