Comparison of University of Wisconsin and St Thomas' Hospital solutions on endothelium-derived hyperpolarizing factor-mediated function in coronary micro-arteries.
BACKGROUND
It is controversial whether coronary endothelial function is impaired after cold exposure to University of Wisconsin (UW) or St. Thomas' Hospital (ST) solution during heart transplantation. We therefore examined the effects of cold storage of coronary micro-arteries with UW or ST solution on endothelium-derived hyperpolarizing factor (EDHF)-mediated function.


METHODS
Porcine and human coronary arteries were immersed in either UW or ST solution at 4 degrees C for 4 hr and then normalized in a wire myograph.


RESULTS
In the rings (normalized diameter: 200-500 microM) precontracted by U46619, EDHF-mediated relaxation and hyperpolarization were initiated by bradykinin (BK) or A23187 in the presence of indomethacin and NG-nitro-L-arginine. In the human coronary arteries, the EDHF-mediated relaxation to BK was reduced by UW solution from 53.2+/-5.6% to 24.0+/-2.7% (P=0.006). The reduced EDHF-mediated relaxation occurred concurrently with the decreased hyperpolarization to BK (17.0+/-1.5 vs. 10.5+/-1.1 mV, n=10, P=0.004) or A23187 in porcine coronary arteries. In the control arteries, K+ channel blockers, either glybenclamide or tetraethylammonium reduced the EDHF-mediated relaxation. After exposure to UW solution, the EDHF-mediated relaxation was further significantly inhibited. In contrast, ST solution did not affect these responses.


CONCLUSIONS
These results show that in coronary micro-arteries, UW, but not ST, solution impairs the EDHF-mediated function and inhibits the Ca2+-activated and ATP-sensitive K+ channels. Our comparative study suggests that ST solution may be superior to UW solution in preserving the EDHF-related endothelial function of coronary micro-arteries.
Department of Surgery, University of Hong Kong, China.
Z D
ZD
Ge
G W
GW
He
D000241:Adenosine / Q000494:pharmacology; D000493:Allopurinol / Q000494:pharmacology; D000818:Animals; D001639:Bicarbonates / Q000494:pharmacology; D001685:Biological Factors / Q000502:physiology*; D002122:Calcium Chloride / Q000494:pharmacology; D003331:Coronary Vessels / Q000502:physiology*; D004730:Endothelium, Vascular / Q000502:physiology; D011464:Epoprostenol / Q000502:physiology; D005978:Glutathione / Q000494:pharmacology; D066298:In Vitro Techniques; D007213:Indomethacin / Q000494:pharmacology; D007328:Insulin / Q000494:pharmacology; D008274:Magnesium / Q000494:pharmacology; D008564:Membrane Potentials; D008833:Microcirculation / Q000502:physiology; D009569:Nitric Oxide / Q000502:physiology; D019335:Nitroarginine / Q000494:pharmacology; D019188:Organ Preservation Solutions; D015221:Potassium Channels / Q000502:physiology; D011189:Potassium Chloride / Q000494:pharmacology; D011887:Raffinose / Q000494:pharmacology; D012965:Sodium Chloride / Q000494:pharmacology; D013552:Swine; D014661:Vasoconstriction
D001639:Bicarbonates; D001685:Biological Factors; D007328:Insulin; D019188:Organ Preservation Solutions; D015221:Potassium Channels; C041711:St. Thomas' Hospital cardioplegic solution; C055206:University of Wisconsin-lactobionate solution; C067410:endothelium-dependent hyperpolarization factor; D019335:Nitroarginine; D009569:Nitric Oxide; D012965:Sodium Chloride; D000493:Allopurinol; D011189:Potassium Chloride; D011464:Epoprostenol; D005978:Glutathione; D008274:Magnesium; D000241:Adenosine; D002122:Calcium Chloride; D011887:Raffinose; D007213:Indomethacin