Hyperoxic and hyperbaric-induced cardioprotection: role of nitric oxide synthase 3. Cardiovasc Res 2006 Oct 01;72(1):143-51
Date
08/26/2006Pubmed ID
16930572DOI
10.1016/j.cardiores.2006.06.031Scopus ID
2-s2.0-33748146058 (requires institutional sign-in at Scopus site) 68 CitationsAbstract
OBJECTIVE: The relative contributions of the fraction of inspired oxygen (FIO2) and atmospheric pressure (ATM) to cardioprotection are unknown. We determined whether the product of FIO2 x ATM (oxygen partial pressure) controls the extent of hyperoxic+hyperbaric-induced cardioprotection and involves activation of nitric oxide synthase (NOS).
METHODS: Adult Sprague Dawley rats (n = 10/gp) were treated for 1 h with (1) normoxia+normobaria (21% O2 at 1 ATM), (2) hyperoxia+normobaria (100% O2 at 1 ATM), (3) normoxia+hyperbaria (21% O2 at 2 ATM) and (4) hyperoxia+hyperbaria (100% O2 at 2 ATM).
RESULTS: Infarct size following 25 min ischemia and 180 min reperfusion was decreased following hyperoxia+normobaria and normoxia+hyperbaria compared with normoxia+normobaria and further decreased following hyperoxia+hyperbaria treatment. l-NAME (200 microM) reversed the cardioprotective effects of hyperoxia+hyperbaria. Nitrite plus nitrate content was increased 2.2-fold in rats treated with normoxia+hyperbaria and hyperoxia+hyperbaria. NOS3 protein increased 1.2-fold and association of hsp90 with NOS3 four-fold in hyperoxic+hyperbaric rats.
CONCLUSIONS: Cardioprotection conferred by hyperoxia+hyperbaria is directly dependent on oxygen availability and mediated by NOS.
Author List
Cabigas BP, Su J, Hutchins W, Shi Y, Schaefer RB, Recinos RF, Nilakantan V, Kindwall E, Niezgoda JA, Baker JEAuthor
John E. Baker PhD Professor in the Surgery department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AnimalsEnzyme Activation
HSP90 Heat-Shock Proteins
Heme Oxygenase-1
Hyperbaric Oxygenation
Male
Myocardial Ischemia
Myocardial Reperfusion
Myocardial Reperfusion Injury
Myocardium
Nitrates
Nitric Oxide
Nitric Oxide Synthase Type III
Oxygen
Perfusion
Rats
Rats, Sprague-Dawley