[Nitroglycerin tolerance aggravates arterial ischemia/reperfusion injury by increasing nitrotyrosine and ONOO- production].
OBJECTIVE
To investigate the influence of nitroglycerin tolerance (NT) on arterial ischemia (90 min) and reperfusion (120 min).


METHODS
Male Sprague-Dawley rats were infused with nitroglycerin (GTN) or saline for 12 h and ascending aorta was rapidly isolated. The isolated aorta was subjected to one of the following treatments: stimulative ischemia/reperfusion, stimulative ischemia/reperfusion (I/R) plus glutathione (GSH, 0.1 mmol/L) during reperfusion, or control solution (Kreb's solution for 3.5 h).


RESULTS
Compared with I/R group, contractile function, vasorelaxation responses to Ach, NO production were significantly decreased and CK, LDH activity as well as nitrotyrosine formation in reperfusion solution were significantly increased in I/R + NT group and these effects could be prevented with addition of GSH in I/R + NT aortas.


CONCLUSIONS
Our results demonstrated that NT could aggravate arterial I/R injury by increasing the production of ONOO- and GSH may play a cardioprotective role against NT-induced myocardial injury by attenuating the formation of ONOO-.
Fan
Qian
Q
Heart Center, Beijing Chaoyang Hospital-Affiliate of Capital University of Medical Sciences, Beijing 100020, China.
Zhang
Lin
L
Gao
Feng
F
Ma
Xin-liang
XL
Cao
Xue-bin
XB
Yang
Xin-chun
XC
D000818:Animals; D001011:Aorta / Q000187:drug effects; D004361:Drug Tolerance; D005978:Glutathione / Q000378:metabolism; D066298:In Vitro Techniques; D008297:Male; D005996:Nitroglycerin / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D015427:Reperfusion Injury / Q000473:pathology / Q000503:physiopathology*; D014661:Vasoconstriction
D005996:Nitroglycerin; D005978:Glutathione