Research Article| Volume 80, ISSUE 2-3, P109-116, September 2001

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Impact of low level laser irradiation on infarct size in the rat following myocardial infarction

  • N. Ad
    Department of Cardiothoracic Surgery, Rabin Medical Center, Sackler School of Medicine, Tel Aviv University, Ramat Aviv, Tel Aviv 69978, Israel
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  • U. Oron
    Corresponding author. Tel.: +972-3-640-9814; fax: +972-3-640-9403
    Department of Zoology, The George S. Wise Faculty of Life Sciences, Tel Aviv University, Ramat Aviv, Tel Aviv 69978, Israel
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      Low energy level irradiation (LLLI) has been found to modulate biological processes. The effect of LLLI on the development of acute myocardial infarction (MI) was investigated following chronic ligation of the left anterior descending (LAD) coronary artery in laboratory rats. The hearts of 22 rats were laser irradiated (LI) using a diode laser (804 nm, 38 mW power output) through the intercostal muscles in the chest following MI and on day 3 post MI. In the control non laser irradiated (NLI) group (19 rats) MI was induced experimentally and laser irradiation was not applied. All rats were sacrificed 21 days post MI. Size, thickness and relative circumferential length of the infarct, as well as other parameters, were determined from histological sections stained with Masson’s trichrome and hearts stained with triphenyl tetrazolium chloride (TTC) using histomorphometric methods. The infarct size (expressed as percent of total left ventricle area) of the LI rats was 10.1±5.8, which was significantly lower (65%; P<0.01) than the infarct size of NLI rats which was 28.7±9.6. Correlatively, the ratio of circumferential length of the infarcted area was significantly lower (2-fold; P<0.01) in the LI rats as compared to the NLI rats. LLLI of the infarcted area in the myocardium of experimentally induced MI rats, at the correct energy, duration and timing, markedly reduces the loss of myocardial tissue. This phenomenon may have an important beneficial effect on patients after acute MI or ischemic heart disease.


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        • Buja L.M.
        Modulation of the myocardial response to ischemia.
        Lab Invest. 1998; 78: 1345-1373
        • Horstick G.
        • Heimann A.
        • Gotze O.
        • et al.
        Intracoronary application of C1 esterase inhibitor improves cardiac function and reduces myocardial necrosis in an experimental model of ischemia and reperfusion.
        Circulation. 1997; 95: 701-708
        • Omerovic E.
        • Bollano E.
        • Basetti M.
        • et al.
        Bioenergetic, functional and morphological consequences of post infarct cardiac remodeling in the rat.
        J Mol Cell Cardiol. 1999; 31: 1685-1695
        • Pfeffer M.A.
        • Braunwald E.
        Ventricular remodeling after myocardial infarction. Experimental observations and clinical implications.
        Circulation. 1990; 81: 1161-1172
        • Roberts C.L.
        • Maclean B.A.D.
        • Braunwald E.
        • Maroko P.R.
        • Kloner R.A.
        Topographic changes in the left ventricle after experimentally-induced myocardial infarction in the rat.
        Am J Cardiol. 1983; 51: 872-876
        • Hochman J.S.
        • Sleeper L.A.
        • Webb J.G.
        • et al.
        Early revascularisation in acute myocardial infarction complicated by cardiogenic shock. SHOCK Investigators. Should we emergently revascularise occluded coronaries for cardiogenic shock.
        New Engl J Med. 1999; 26: 625-634
        • Losordo D.W.
        • Vale P.R.
        • Symes J.F.
        • et al.
        Gene therapy for myocardial angiogenesis: initial clinical results with direct myocardial injection of phVEGF165 as sole therapy for myocardial ischemia.
        Circulation. 1998; 98: 2800-2804
        • Woo Y.J.
        • Zhang J.C.L.
        • Vijayasarathy C.
        • et al.
        Recombinant adenovirus-mediated cardiac gene transfer of superoxide dismutase and catalase attenuates postischemic contractile dysfunction.
        Circulation. 1998; 98: 255-261
        • Kessler P.D.
        • Byrne B.Y.
        Myoblast cell grafting into heart muscle: cellular biology and potential application.
        Ann Rev Physiol. 1999; 61: 219-242
        • Li Q.K.
        • Mickle D.A.G.
        • Weisel R.D.
        • Zhang Ji.
        • Mohabeer M.K.
        In vivo survival and function of transplanted rat cardiomyocytes.
        Circ Res. 1996; 78: 283-288
        • Taylor D.A.
        • Atkin B.Z.
        • Hungspreugs P.
        • et al.
        Regenerating functional myocardium: improved performance after skeletal myoblast transplantation.
        Nat Med. 1998; 4: 929-934
        • Conlan M.J.
        • Rapley J.W.
        • Cobb C.M.
        Biostimulation of wound healing by low energy laser irradiation. A review.
        J Clin Periodontol. 1996; 23: 492-496
        • Karu T.
        The science of low-power laser therapy. Gordon and Breach, Amsterdam, Delhi1998
        • Morimoto Y.
        • Arai T.
        • Kikuchi M.
        • Nakajima S.
        • Nakamura H.
        Effect of low intensity argon laser irradiation on mitochondria respiration.
        Lasers Surg Med. 1994; 15: 191-199
        • Yu W.
        • McGowan M.
        • Ippolito K.
        • Lanzafame R.J.
        Photomodulation of oxidative metabolism and electron chain enzymes in rat liver mitochondria.
        Photochem Photobiol. 1997; 66: 866-871
        • Bibikova A.
        • Oron U.
        Attenuation of the process of muscle regeneration in the toad gastrocnemius muscle by low energy laser irradiation.
        Lasers Surg Med. 1994; 14: 355-361
        • Bibikova A.
        • Oron U.
        Promotion of muscle regeneration in the toad (Bufo viridis) gastrocnemius muscle by low energy laser irradiation.
        Anat Rec. 1993; 235: 374-380
        • Weiss N.
        • Oron U.
        Enhancement of muscle regeneration in the rat gastrocnemius muscle by low energy laser irradiation.
        Anat Embryol. 1992; 186: 497-503
        • Bibikova A.
        • Belkin A.
        • Oron U.
        Enhancement of angiogenesis in regenerating gastrocnemius muscle of the toad (Bufo viridis) by low energy laser irradiation.
        Anat Embryol. 1994; 190: 597-602
        • Ben-Dov N.
        • Shefer G.
        • Irintchev A.
        • Wernig A.
        • Oron U.
        • Halevy O.
        Low energy laser irradiation affects cell proliferation and differentiation in vitro.
        Biochim Biophys Acta. 1999; 1448: 372-380
        • Zhu Q.
        • Yu W.
        • Yang X.
        • Hicks G.L.
        • Lanzafame R.J.
        • Wang T.
        Photoirradiation improved functional preservation of the isolated rat heart.
        Lasers Surg Med. 1997; 20: 332-339
        • Weibel E.R.
        Stereological methods, theoretical foundations. Academic Press, London1980
        • Sokal R.R.
        • Rohlf F.J.
        Biometry. 2nd ed. W.H. Freeman, London1981