[The effect of He-Ne laser radiation on myocardium mechanical activity in rats]

In isolated papillary muscles, a 5-minute irradiation with the He-Ne-laser Shuttle-1 enhances the maximal strength of isometric contraction and acceleration of relaxation. In physiological mode of mechanical loads, the irradiation with the laser red light enhances the myocardium contractability at all final systolic lengths with simultaneous enhancement of the isometric relaxation velocity at great systolic lengths and a deceleration of the relaxation at lesser lengths. Under the He-Ne-laser effect, restoration of rhythm-inotropic relationships occurred in the myocardium.