title: Blue laser light increases perfusion of a skin flap via release of nitric oxide from hemoglobin.
abstract: It has recently been shown that nitrosyl complexes of hemoglobin (NO-Hb) are sensitive to low-level blue laser irradiation, suggesting that laser irradiation can facilitate the release of biologically active nitric oxide (NO), which can affect tissue perfusion. The aim of this study was to evaluate the therapeutic value of blue laser irradiation for local tissue perfusion after surgical intervention. Blood was withdrawn from a rat, exposed to NO and infused back to the same rat or used for in vitro experiments. In vitro, an increase of NO-Hb levels (electron paramagnetic resonance spectroscopy) up to 15 microM in rat blood did not result in the release of detectable amounts of NO (NO selective electrode). Blue laser irradiation of NO-Hb in blood caused decomposition of NO-Hb complexes and release of free NO. Systemic infusion of NO-Hb in rats affected neither systemic circulation (mean arterial pressure) nor local tissue perfusion (Doppler blood flow imaging system). In contrast, a clear enhancement of local tissue perfusion was observed in epigastric flap when elevated NO-Hb levels in blood were combined with local He-Cd laser irradiation focused on the left epigastric artery. The enhancement of regional tissue perfusion was not accompanied by any detectable changes in systemic circulation. This study demonstrates that blue laser irradiation improves local tissue perfusion in a controlled manner stimulating NO release from NO-Hb complexes.
authors.affiliation: Ludwig Boltzmann Institute for Experimental and Clinical Traumatology in the AUVA Research Center, Vienna, Austria.
authors.forename: Rainer
authors.initials: R
authors.lastname: Mittermayr
authors.forename: Anatoly
authors.initials: A
authors.lastname: Osipov
authors.forename: Christina
authors.initials: C
authors.lastname: Piskernik
authors.forename: Susanne
authors.initials: S
authors.lastname: Haindl
authors.forename: Peter
authors.initials: P
authors.lastname: Dungel
authors.forename: Carina
authors.initials: C
authors.lastname: Weber
authors.forename: Yuri A
authors.initials: YA
authors.lastname: Vladimirov
authors.forename: Heinz
authors.initials: H
authors.lastname: Redl
authors.forename: Andrey V
authors.initials: AV
authors.lastname: Kozlov
mesh_terms: D000818:Animals; D004578:Electron Spin Resonance Spectroscopy; D006454:Hemoglobins / Q000737:chemistry* / Q000378:metabolism / Q000528:radiation effects*; D007700:Kinetics; D007834:Lasers; D008027:Light; D008297:Male; D009569:Nitric Oxide / Q000032:analysis / Q000378:metabolism*; D010477:Perfusion; D051381:Rats; D017207:Rats, Sprague-Dawley; D012039:Regional Blood Flow; D013524:Surgical Flaps / Q000098:blood supply*; D014664:Vasodilation / Q000502:physiology / Q000528:radiation effects
chemical_list: D006454:Hemoglobins; D009569:Nitric Oxide