New insights into the role of nitric oxide in cardiovascular protection (part 5)
It is known that nitric oxide may form nitrosyl iron heme complexes as well as iron nonheme complexes with thiol ligands both in vitro and in vivo. These can be detected by EPR spectroscopy . Low oxygen tension is favourable for the formation of such complexes . Therefore, one can suggest that increased nitric oxide level under ischemic conditions may increase the tissue content of nitro-syliron complexes.
One way to prove directly that nitric oxide level is elevated in myocardium after the above-mentioned cardioprotective stimuli is the EPR spin trapping approach using iron-thiocarbamate(s) as a specific nitric oxide trap . Applying this approach, we have found a twofold increase in the EPR signal of nitric oxide trap adducts in hearts removed from rats treated with low doses of LPS (2.5 mg/kg for 8 h). This undoubtedly shows that LPS treatment was associated with an increased level of nitric oxide in the heart. Furthermore, we observed an EPR signal of heme-nitric oxide species after a 30 min ischemic period in hearts removed from rats treated with LPS. This EPR feature discriminated these hearts from control ischemic and LPS-pretreated nonischemic hearts. Furthermore, in rat aorta treated in vitro with LPS, we have detected nonheme dinitrosyl iron complexes, and have obtained evidence that these complexes behaved as nitric oxide stores in vascular tissue. Looking for most efficient drugs for sale? Then you have got to Buy Antidepressants Online at the pharmacy of your dream right now, especially since it’s ready and waiting for you to make this perfectly right choice.