Effect of ATP-potassium channel opener nicorandil on long-term cardiac preservation.
BACKGROUND
ATP-sensitive potassium channels have been shown to be one of the important protective mechanisms for the ischemic myocardium. The purpose of this study was to evaluate the protective effect of nicorandil, an ATP-sensitive potassium channel opener, on myocardium during 6 hours hypothermic preservation.


METHODS
Preserved rat hearts were randomly divided into 4 groups according to cardioplegia and preservation protocols as follows: (1) histidine-tryptophan-ketoglutarate solution (HTK) for both cardioplegic and immersing solutions (group A); (2) nicorandil-added HTK for cardioplegic solution and nicorandil-free HTK for immersing solution (group B); (3) nicorandil-free HTK for cardioplegic solution and nicorandil-added HTK for immersing solution (group C); and (4) nicorandil-added HTK for both cardioplegic and immersing solutions (group D).


RESULTS
The recovery of postischemic cardiac function, including left ventricular developed pressure and end-diastolic pressure, was significantly improved in group B and group C as compared with the other groups (p<0.05). Postischemic intracellular calcium concentration was significantly lower in group B and group C than in group A (p<0.05).


CONCLUSIONS
We concluded that nicorandil-induced hyperpolarizing arrest could reduce ischemia-derived myocyte injury and inhibit the influx of calcium into the myocytes in long-term cardiac preservation.
Hachida
M
M
Department of Cardiovascular Surgery, The Heart Institute of Japan, Tokyo Women's Medical College.
Lu
H
H
Ohkado
A
A
Gu
H
H
Zhang
X L
XL
Furukawa
H
H
Nakanishi
T
T
Koyanagi
H
H
D000818:Animals; D004305:Dose-Response Relationship, Drug; D006321:Heart; D006324:Heart Arrest, Induced; D007036:Hypothermia, Induced; D008297:Male; D020108:Nicorandil / Q000494:pharmacology*; D009926:Organ Preservation; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D014665:Vasodilator Agents / Q000494:pharmacology*
D014665:Vasodilator Agents; D020108:Nicorandil