Effect of low intensity pulse-modulated electromagnetic radiation on activity of alkaline phosphatase in blood serum

The change in alkaline phosphotase activity in vitro with frequencies modulation at low intensity of pulse-modulated electromagnetic radiation was experimentally shown (EMR, 2375 MHz, intensity: 0.8, 8.0; 40.0 microW/cm2; range modulation: 30-310 Hz; time of interaction: 1-3 min). Revealed effects could be regarded as an evidence of informative character of interaction of modulated EMR.     

Association of myocardial glutamate and aspartate pool and functional recovery of postischemic heart

The effect of low flow ischemia and subsequent reperfusion with 5.5 mM glucose or 5 mM acetate on energy metabolism and catabolism of myocardial glutamate and aspartate was studied in isolated perfused guinea pig hearts. Reperfusion with acetate was followed by low recovery of the cardiac contractile function associated with a great rise in isovolumic end-diastolic pressure. It was combined with more profound losses of tissue adenine nucleotides and the total Cr compared to reperfusion with glucose. The total glutamate and aspartate pool decreased more than two-fold compared to the initial one regardless of substrate. However, glutamate content was reduced by 58 and 38% with acetate and glucose, respectively. The expenditure of both amino acids was caused by alanine formation stimulated by glycolysis/glycogenolysis. The remaining glutamate and aspartate pool in the reperfused hearts positively correlated with adenine nucleotides (r = 0.62), the total creatine (r = 0.65), and the recovery of contractile function (r = 0.64). The results suggest that the glutamate and aspartate pool may be of critical importance for postischemic functional and metabolic recovery of the heart.     

Fasudil prevents KATP channel-induced improvement in postischemic functional recovery

Whereas activation of ATP-dependent potassium (K(ATP)) channels greatly improves postischemic myocardial recovery, the final effector mechanism for K(ATP) channel-induced cardioprotection remains elusive. RhoA is a GTPase that regulates a variety of cellular processes known to be involved with K(ATP) channel cardioprotection. Our goal was to determine whether the activity of a key rhoA effector, rho kinase (ROCK), is required for K(ATP) channel-induced cardioprotection. Four groups of perfused rat hearts were subjected to 36 min of zero-flow ischemia and 44 min of reperfusion with continuous measurements of mechanical function and (31)P NMR high-energy phosphate data: 1) untreated, 2) pinacidil (10 microM) to activate K(ATP) channels, 3) fasudil (15 microM) to inhibit ROCK, and 4) both fasudil and pinacidil. Pinacidil significantly improved postischemic mechanical recovery [39 +/- 16 vs. 108 +/- 4 mmHg left ventricular diastolic pressure (LVDP), untreated and pinacidil, respectively]. Fasudil did not affect reperfusion LVDP (41 +/- 13 mmHg) but completely blocked the marked improvement in mechanical recovery that occurred with pinacidil treatment (54 +/- 15 mmHg). Substantial attenuation of the postischemic energetic recovery was also observed. These data support the hypothesis that ROCK activity plays a role in K(ATP) channel-induced cardioprotection.     

The role of low intensity red luminescent radiation in the control of Arabidopsis thaliana morphogenesis and hormonal balance

The effects of low intensity red luminescent radiation emitted by the polyethylene light-correcting film due to the conversion of UV-A radiation on Arabidopsis thaliana (L.) Heynh. morphogenesis and hormonal balance were studied. Wild-type Ler plants and two mutants, hy3 and hy4, displaying disturbances in the synthesis of phytochrome B and cryptochrome 1, respectively, were compared. In wild-type and hy4 plants grown under the light-correcting film, growth and development were substantially accelerated, whereas, in hy3 plants, they were retarded. These changes were correlated with changes in the levels of endogenous hormones, both growth activators and inhibitors. We concluded that low intensity red luminescent radiation affected the plant hormonal balance. In its turn, the changes in the hormone ratios, growth stimulators and inhibitors, affected the rate of plant growth and their productivity.     

Glucose requirement for postischemic recovery of perfused working heart

The quantitative importance of glycolysis in cardiomyocyte reenergization and contractile recovery was examined in postischemic, preload-controlled, isolated working guinea pig hearts. A 25-min global but low-flow ischemia with concurrent norepinephrine infusion to exhaust cellular glycogen stores was followed by a 15-min reperfusion. With 5 mM pyruvate as sole reperfusion substrate, severe contractile failure developed despite normal sarcolemmal pyruvate transport rate and high intracellular pyruvate concentrations near 2 mM. Reperfusion dysfunction was characterized by a low cytosolic phosphorylation potential [( ATP]/[( ADP][Pi]) due to accumulations of inorganic phosphate (Pi) and lactate. In contrast, with 5 mM glucose plus pyruvate as substrates, but not with glucose as sole substrate, reperfusion phosphorylation potential and function recovered to near normal. During the critical ischemia-reperfusion transition at 30 s reperfusion the cytosolic creatine kinase appeared displaced from equilibrium, regardless of the substrate supply. When under these conditions glucose and pyruvate were coinfused, glycolytic flux was near maximum, the glyceraldehyde-3-phosphate dehydrogenase/3-phosphoglycerate kinase reaction was enhanced, accumulation of Pi was attenuated, ATP content was slightly increased, and adenosine release was low. Thus, glucose prevented deterioration of the phosphorylation potential to levels incompatible with reperfusion recovery. Immediate energetic support due to maximum glycolytic ATP production and enhancement of the glyceraldehyde-3-phosphate dehydrogenase/3-phosphoglycerate kinase reaction appeared to act in concert to prevent detrimental collapse of [ATP]/[( ADP][Pi]) during creatine kinase dysfunction in the ischemia-reperfusion transition. Dichloroacetate (2 mM) plus glucose stimulated glycolysis but failed fully to reenergize the reperfused heart; conversely, 10 mM 2-deoxyglucose plus pyruvate inhibited glycolysis and produced virtually instantaneous de-energization during reperfusion. The following conclusions were reached. (1) A functional glycolysis is required to prevent energetic and contractile collapse of the low-flow ischemic or reperfused heart (2). Glucose stabilization of energetics in pyruvate-perfused hearts is due in part to intensification of glyceraldehyde-3-phosphate dehydrogenase/3-phosphoglycerate kinase activity. (3) 2-Deoxyglucose depletes the glyceraldehyde-3-phosphate pool and effects intracellular phosphate fixation in the form of 2-deoxyglucose 6-phosphate, but the cytosolic phosphorylation potential is not increased and reperfusion failure occurs instantly. (4) Consistent correlations exist between cytosolic ATP phosphorylation potential and reperfusion contractile function. The findings depict glycolysis as a highly adaptive emergency mechanism which can prevent deleterious myocyte deenergization during forced ischemia-reperfusion transitions in presence of excess oxidative substrate.     

Effects of low intensity laser (632.8 nm) and ultraviolet radiation on spectral properties and functional activity of human ceruloplasmin

Photoinduced changes of human ceruloplasmin (hCp) under laser and ultraviolet (UV) radiation have been studied. A complex character of hCp spectral modifications points to a different degree of the protein molecule folding. After the influence of UV radiation (240-390 nm) in a dose range 906-4530 J/m2 the decrease of oxidase hCp activity was registered. These changes are thought to be connected with modification of the conformation of hCp active centre or copper reduction that was confirmed by the decrease of optical density at 610 nm. An inactivation constant (kf = 3.8 x 10(-4) 1/s) and a photoinactivation quantum yield (1.4 x 10(-4)) were calculated. Kinetic dependencies of o-phenilen-diamine oxidation by intact and UV-modified glycoprotein do not correspond to Michaelis-Menten equation. UV radiation in a dose range 151-4530 J/m2 induced increasing of ceruloplasmin superoxiddismutase activity. The influence of He-Ne laser radiation (1.3 mW; lambda = 632.8 nm, exposure time from 1 up to 30 min) leads to the raise of the hCp functional activity; superoxiddismutase activity changes more significantly. Possible photophysical and photochemical processes in hCp molecule, leading to photomodification and changes of protein functional activity have been represented on the scheme.     

Propionyl-L-carnitine effects on postischemic recovery of heart function and substrate oxidation in the diabetic rat

Previous studies have shown that propionyl-L-carnitine (PLC) can exert cardiac antiischemic effects in models of diabetes. In the nonischemic diabetic rat heart, PLC improves ventricular function secondary to stimulation in the oxidation of glucose and palmitate. Whether this increase in the oxidation of these substrates can explain the beneficial effects of PLC in the ischemic reperfused diabetic rat heart has yet to be determined. Diabetes was induced in male Sprague-Dawley rats by an intravenous injection of streptozotocin (60 mg/kg). Treatment was initiated by supplementing the drinking water with propionyl-L-carnitine at the concentration of 1 g/L. After a 6-week treatment period, exogenous substrate oxidation and recovery of mechanical function following ischemia were determined in isolated working hearts. In aerobically perfused diabetic hearts, compared with those of controls, rates of glucose oxidation were lower, but those of palmitate oxidation were similar. Diabetes was also characterized by a pronounced decrease in heart function. Following treatment with by propionyl-L-carnitine, however, there was a marked increase in rates at which glucose and palmitate were oxidized by diabetic hearts and a significant improvement in heart performance. Postischemic recovery of function in diabetic hearts was also improved with PLC. This improvement in contractile function was accompanied by an increase in both glucose and palmitate oxidation. Our findings show that postischemic diabetic rat heart can be improved following chronic PLC treatment. This beneficial effect of propionyl-L-carnitine can be explained, in part, by an improvement in the oxidation of glucose and palmitate.     

Effect of low intensity of electromagnetic radiation in the centimeter and millimeter range on proliferative and cytotoxic activity of murine spleen lymphocytes

It was found that single total-body exposure to electromagnetic centimeter waves (8.15-18 GHz, 1 microW/cm2, 5 h) stimulated the proliferation of mouse T and B splenic lymphocytes. The same effects were observed upon in vivo treatment of rats for 5 h with millimeter waves (42.2 GHz, amplitude modulation 10 Hz, 1 microW/cm2). The whole-body irradiation with centimeter or millimeter waves did not cause any significant changes in natural activity of killer cells. The cellular responses induced by the irradiation of isolated animal cells in vitro did not coincide with those revealed after the total-body irradiation of animals. Thus, the in vitro irradiation of natural killer cells to millimeter waves for 1 h increased their cytotoxic activity whereas, after treatment to centimeter waves for the same time, the activity of killer cells did not change. On the contrary, irradiation of T and B lymphocytes with millimeter waves (42.2 GHz, amplitude modulation 10 Hz, 1 microW/cm2, 1 h) suppressed the blasttransformation of cells. The results show a higher immunostimulative potential of centimeter waves as compared to millimeter waves.     

Effect of heparin on the antiradiation activity of cystamine, decreasing with a reduction in radiation intensity

It was shown that a single injection of heparin (250 units/kg) 15 min and 24 h before irradiation potentiated a slight radioprotective effect of cystamine (dichlorohydrate, 170 mg/kg) which was registered after the administration thereof to mice 30 min before irradiation with an absolutely lethal dose at a dose rate of 0.0025 Gy/c.     

Effect of low intensity pulsed laser radiation of basic parameters of aging in Drosophila melanogaster

The effect of the low-intensive impulse laser radiation (LILR) on the life span of Drosophila melanogaster has been studied. The flies at various stages of their life (larvae and imago) were exposed to LILR. The estimation of the effect of LILR was carried out on the basis of the analysis of the basis parameters of aging. We found out increasing as well as shortening effects of the life span. The direction of the effect depends on parameters of radiation, stage of development of irradiated individuals and their sex.     

Effect of streptomycin sulfate on the process of higher nervous activity recovery in dogs in the postanesthesia period]

The effect of streptomycin on recovery of the higher nervous activity during the postanesthesia period was studied on 3 dogs with the method of the conditioned reflexes. It was found that streptomycin sulphate administered in a dose of 25 mg per 1 kg body weight induced no changes in the conditioned reflexes of the non-anesthetized animals. After ether anesthesia disorders in the conditioned and unconditioned reflexes, as well as differentiation was observed during the postanesthesia period. On an average they normalized in 7, 6 and 2 days respectively from the moment of anesthesia. When streptomycin sulphate was used during the post anesthesia period, both the strength and the character of the disorders in the conditioned reflexes changed. In this case recovery of the conditioned and unconditioned reflexes was registered in 2 days, while that of the differential inhibition was registered in 3--7 days from the moment of anesthesia.     

Restoration of blood supply and the intensity of phospholipid metabolism in different rat brain regions during the postischemic period]

Fifteen min after resumption of the blood flow in the common carotid arteries the arrest of which was caused by ligation, a considerable intensification of the blood supply in the hemispheres, diencephalon and the midbrain and its simultaneous reduction in the cerebellum and the medulla oblongata occurred. Sixty min later the cerebral blood supply in all the parts of the brain under study recovered completely, except the hemispheres. The complete postischemic recovery of the phospholipid metabolism intensity occurred in the brain regions showing a considerable diminution of the phospholipid metabolism during the ischemic period.     

Effect of extremely high frequency electromagnetic radiation of low intensity on parameters of humoral immunity in healthy mice

The modification of indices of the humoral immune response to thymus-dependent antigen (sheep erythrocytes) after a whole-body exposure of healthy mice to low-intensity extremely-high-frequency electromagnetic radiation was studied. Male NMRI mice were exposed in the far-field zone of horn antenna at a frequency of 42.0 GHz and energy flux density of 0.15 mW/cm2 under different regimes: once for 20 min, for 20 min daily during 5 and 20 successive days before immunization, and for 20 min daily during 5 successive days after immunization throughout the development of the humoral immune response. The intensity of the humoral immune response was estimated on day 5 after immunization by the number of antibody-forming cells of the spleen and antibody titers. Changes in cellularity of the spleen, thymus and red bone marrow were also assessed. The indices of humoral immunity and cellularity of lymphoid organs changed insignificantly after acute exposure and series of 5 exposures before and after immunization of the animals. However, after repeated exposures for 20 days before immunization, a statistically significant reduction of thymic cellularity by 17.5% (p < 0.05) and a decrease in cellularity of the spleen by 14.5% (p < 0.05) were revealed. The results show that low-intensity extremely-high-frequency electromagnetic radiation with the frequency and energy flux density used does not influence the humoral immune response intensity in healthy mice but influences immunogenesis under multiple repeated exposures.     

Immunocorrective effect of low intensity radiation of ultrahigh frequency on carcinogenesis in mice

The effect of low-intensity centimeter electromagnetic waves (8.15-18 GHz, 1 microW/cm2, 1.5 h daily, 20 days) on the production of tumor necrosis factor, intreleukin-2, and interleukin-3 and the expression of the heat shock protein 72 in healthy and tumor-bearing mice was measured. A significant increase in tumor necrosis factor production and a slight reduction of interleukin-2 concentration were observed after exposure to microwaves; we consider these effects as adaptive response. The interleukin-3 production in healthy mice was not affected by microwaves. Low-intensity centimeter waves induced antitumoral resistance in tumor-bearing mice. Thus, exposure of tumor-bearing mice led to a significant rise in the tumor necrosis factor production and the normalization of both interleukin-2 and interleukin-3 concentration. We assume that the significant immunomodulating effect of low-density centimeter microwaves can be used for immunocorrection and suppression of tumor growth.     

Effect of Tanakan on postischemic activity of protein synthesis machinery in the rat brain

A growing body of evidence supports the role of free radicals in triggering the functional and metabolic disturbances following transient cerebral ischemia. This study was designed to evaluate whether the extent of reperfusion-induced inhibition of protein synthesis initiation as well as tissue injury can be reduced by Tanakan (Ginkgo biloba extract, EGb 761) (Beaufour-Ipsen Industrie). Rats received Tanakan in the dose of 40 mg/kg/day for 7 days before surgical intervention. Transient forebrain ischemia was induced by 4-vessel occlusion. Rats were subjected to 20 min of ischemia followed by 30 min, 4 h or 7 days of reperfusion. Protein synthesis rate, reinitiation ability and neurodegeneration in the frontal cortex and hippocampus were measured by the incorporation of radioactively labelled leucine into polypeptide chains in postmitochondrial supernatants and by Fluoro-Jade B staining. The protective effect was observed, concerning both the protein synthesis and the number of surviving neurons, in the Tanakan-treated groups. Tanakan significantly reduced the ischemia/reperfusion-induced inhibition of translation in the neocortex as well as in the highly sensitive hippocampus. Our results indicate that free radicals play an important role in the development of reperfusion-induced injury, and the treatment of ischemic and reperfused brain with free radical scavengers may reduce the severity of reperfusion damage.     

Insulin improves postischemic recovery of function through PI3K in isolated working rat heart

Insulin improves contractile function after ischemia, but does not increase glucose uptake in the isolated working rat heart. We tested the hypothesis that the positive inotropic effect of insulin is independent of the signaling pathway responsible for insulin-stimulated glucose uptake. We inhibited this pathway at the level of phosphatidyl inositol 3-kinase (PI3K) with wortmannin. Hearts were perfused for 70 min at physiological workload with Krebs-Henseleit buffer containing [2-³H] glucose (5 mM, 0.05 Ci/ml) and oleate (0.4 mM, 1% BSA) in the presence (WM, n = 5) or absence (control, n = 7) of wortmannin (WM, 3 mol/L). After 20 min, hearts were subjected to 15 min of total global ischemia followed by 35 min of reperfusion. Insulin (1 mU/ml) was added at the beginning of reperfusion (WM + insulin n = 8, insulin n = 8). Cardiac power before ischemia was 8.1 ± 0.7 mW. Recovery of contractile function after ischemia was significantly increased in the presence of insulin (73.5 ± 8.9% vs. 38.5 ± 6.7%, p < 0.01). The addition of wortmannin completely abolished the effect of insulin on recovery (32.6 ± 6.4%). Glucose uptake was 1.84 ± 0.32 mol/min/g dry before ischemia and was slightly elevated during reperfusion (2.68 ± 0.35 mol/min/g dry, n.s.). Insulin did not affect postischemic glucose uptake. In the presence of wortmannin, glucose uptake was lowest during reperfusion (n.s.). The results suggest that PI3K is involved in the insulin-induced improvement in postischemic recovery of contractile function. This effect of insulin is independent of its effect on glucose uptake.