[Effects of diazoxide on the mitochondrial ultrastructure and permeability in donor rat myocardium].
OBJECTIVE
To investigate the effect of diazoxide (DE) on the myocardial ultrastructure and opening of maitochondrial permeability transition pore (MPTP) in donor rat heart suffered from long-term hypothermic preservation.


METHODS
The Langendorff model of isolated rat heart was used. The hearts were stored in 4 degrees C Celsior solution containing different concentration of DE (15, 30, or 45 micromol/L) for 9 h followed by 60 min of reperfusion. The recovery of rate-pressure product (RPP) was observed. The opening of MPTP and myocardial mitochondria ultrastructure were also evaluated.


RESULTS
(1) As compared with the celsior solution preserved group, DE (30 micromol/L) increased recovery of RPP during reperfusion and inhibited the opening of MPTP. DE also alleviated the myocardial mitochondrial ultrastucture damage induced by long-term hypothermic preservation. (2) The above effects of DE were attenuated by a mitoK(ATP) channel inhibitor 5-hydroxydecanoate and a MPTP opener atractyloside.


CONCLUSIONS
In the donor rat heart, DE protects myocardial mitochondria ultrastructure against long-term hypothermic preservation injury via inhibiting the opening of MPIP.
Hu
Pei-lin
PL
Department of Physiology, Hangzhou Normal University, Hangzhou 310036, China.
Zheng
Ming-zhi
MZ
Jiang
Jian-ping
JP
Chen
Wen-liang
WL
Chen
Ying-ying
YY
Shen
Yue-liang
YL
D000818:Animals; D015925:Cryopreservation; D003981:Diazoxide / Q000494:pharmacology*; D006321:Heart; D066298:In Vitro Techniques; D008297:Male; D008929:Mitochondria, Heart / Q000502:physiology / Q000648:ultrastructure*; D033681:Mitochondrial Membrane Transport Proteins / Q000187:drug effects* / Q000378:metabolism; D000083162:Mitochondrial Permeability Transition Pore; D019188:Organ Preservation Solutions / Q000494:pharmacology; D015221:Potassium Channels / Q000378:metabolism; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley
D033681:Mitochondrial Membrane Transport Proteins; D000083162:Mitochondrial Permeability Transition Pore; D019188:Organ Preservation Solutions; D015221:Potassium Channels; C117780:mitochondrial K(ATP) channel; D003981:Diazoxide