CLINICS 2011;66(7):1237-1245 The therapeutic effect of PEMF on reproduction Kumar S et al. Figure 8 - The effect of an electromagnetic field on testosterone production. The bars represent the mean values (¡SEMs). The statistical significance between the values of the sham and exposure groups is indicated by an asterisk (p,0.05). increased. Therefore, apoptosis is considered to be involved in the impairment of spermatogenesis and the seminiferous tubules. It is apparent from our data that a 2.45-GHz frequency increases caspase activity and decreases melatonin levels. These effects are indications of increased apoptosis and, hence, cancer promotion, which affects fertility. These effects were controlled by the administration of PEMF. Previously, our laboratory reported increased levels of PKC and ODC, changes in the levels of antioxidant enzymes (GPx, CAT, and SOD), micronucleus formation, and many other related changes.32,33 The present work supports these findings and others.41 Von Wilmsdorff et al42 hypothesized that brain behavioral modifications due to kainic acid treatment cause sex-specific responses via the hypothala- mic-pituitary-adrenal-axis. Such effects may be achieved through either a chemical or radiation-based treatment, which suggests that the effects are mediated by the higher brain centers and are transferred to the reproductive system, thereby affecting the testosterone and sperm counts through the endocrine system. The exposure of a biological system to a microwave causes a weakly induced signal near the cellular boundary. Energy from a coherent signal penetrates the body, with amplification derived from noise via stochastic phenomena. Thus, the signal can circumvent the barrier height of the plasma membrane (,105 V/m), which may cause DNA damage (strand breaks). This signal may also provide sufficient energy to exacerbate silent mutations existing in biological systems. ROS overproduction is inhibited by the application of a pulsed electromagnetic field (100 Hz, magnetic component), which provides a free electron and thus eliminates the effect of the stressor. Triplet states can be transformed into singlet states via spin-lattice relaxation, which originates in fluctuating local magnetic fields around the electron (because of its random motion).43 In fact, many medical devices used in medical therapies generate circulating currents that trigger cellular, hormonal, and behavioral responses. Wolsko et al44 demonstrated that PEMF relieves or eliminates pain through a mechanism mediated by Ca2+ ion channels. Luo et al45 found that metal ions are necessary for enzymatic activity, and, thus, pulsed electromagnetic field are able to influence the catalytic activities of enzymes. Pulsed electromagnetic therapy is believed to have beneficial effects on tissue growth and repair, probably via alterations in the cellular microenvironment.46 A low-level alternating electromagnetic field (,50 Hz) has also been reported to have a healing effect on spinal cord injury.47 When a microwave field penetrates a biological body, it induces endogenous physiological processes. The major difference between the EMF generated from a 2.45-GHz source and that of the pulsed electromagnetic fields (100 Hz) is that the latter induces a circulating electric current in the tissue because of its constantly changing magnetic flux,29 thereby scavenging the free radical. Free radical formation also occurs at other microwave frequencies, which suggests that this phenomenon occurs generally. The destressor 1243 Figure 9 - A pathway describing the mechanism of a pulsed electromagnetic field.