Hypertensive SHR male rats were irradiated by a photon light-emitting diode matrix with a maximum
irradiation at 612 nm with dose 1.44 J/cm<sup>2</sup> per day . After a course of irradiation (13 days) the rhythmoinothropic
characteristics of cardiac muscle significantly improved. Morphological analysis shown considerable changes in the
structure of sarcoplasmic reticulum (SR), i.e. area of SR profiles increased more than twofold compared to control.
This suggests a proportional increase in ability of SR to absorb calcium, due to both an increase in its buffer capacity
and possibly, an improved functioning of Ca<sup>2+</sup> ATPase of the reticulum. This could lead to an improvement in
calcium homeostasis in the myocytes, and explain the improvement of the characteristics of cardiac muscle
contraction-relaxation cycle. Furthermore, changes were observed in proportions of the myocardium capillaries
(increased by 75%; compared to control, p<0.001) and in the area of mitochondrial profiles of the myocytes
(increased by 13%, p<0.05). This lead to of more active metabolic processes and an energy rise occurring in
myocardial cells after photon radiation treatment.
We propose a "useful sun" strategy with application of a photoluminophore that absorbs a part of the UV component of
the sunlight and converts it into the visible light. As a result, the "harmful" UV sun radiation becomes useful. The
present study was designed to determine the effect of additional luminescent radiation with λ<sub>m</sub>=626nm on the physical
endurance in 12-week-old male mice. Four groups of animals were used: Control I, intact animals; Control II, exposure
to standard artificial day light 5 B<sub>T/M2</sub>; Control III, exposure to solar radiation with absorbed UV-component; and
Experiment, exposure to converted solar radiation with an additional orange-red luminescent component in the range of
603-637 nm (0.11 J/cm<sup>2</sup> per day). The experimental group showed a significant increase (by more than 50%) in
swimming time to exhaustion as compared to Control III. No significant difference in physical endurance was found
between Control III and Control II. These results suggest that improvement in swimming endurance by the solar light is
due to an additional orange-red luminescent component in the range of 603-637 nm.