Effect of alternating the magnetic feld on phosphate metabolism in the nervous system of Helix pomatia

The effect of extremely low frequency magnetic felds (50 Hz, 0.5 mT) - ELF-MF, on phosphate metabolism has been studied in the isolated ganglions of the garden snail Helix pomatia, after 7 and 16 days of snail exposure to ELF-MF. The infuence of ELF-MF on the level of phosphate compounds and intracellular pH was monitored by 31P NMR spectroscopy. Furthermore, the activity of enzymes involved in phosphate turnover, total ATPases, Na+/K+-ATPase and acid phosphatase has been measured. The exposure of snails to the ELF-MF for the period of 7 days shifted intracellular pH toward more alkaline conditions, and increased the activity of investigated enzymes. Prolonged exposure to the ELF-MF for the period of 16 days caused a decrease of PCr and ATP levels and decreased enzyme activity, compared to the 7-day treatment group. Our results can be explained in terms of: 1. increase in phosphate turnover by exposure to the ELF-MF for the period of 7 days, and 2. adaptation of phosphate metabolism in the nervous system of snails to prolonged ELF-MF exposure.

The Effect of Ginkgo Biloba Extract on Hypoxic Fraction of C3H Mouse Fibrosarcoma / 대한치료방사선과학회지

PURPOSE: To investigate the effect of Ginkgo biloba extract (GBE) on hypoxic cell fraction and metabolic status in fibrosarcoma (FSa II) of C3H mouse. MATERIALS AND METHODS: Fibrosarcoma (Fsa II), 6mm in diameter, growing in the right hindleg muscle of C3H mouse was used for estimation of hypoxic cell fraction using comparison of TCD50. Radiation was given one hour after administrationof GBE (100 mg/Kg, i.p.) with or without priming dose of GBE (100 mg/Kg, i.p.) given 24 hours earlier. Radiation was also given under air breathing condition or clamp hypoxia withour GBE as controls. 31P NMR spectroscopy was performed before and one hour after administration of GBE with or without priming dose of GBE. RESULTS: TCD50/120's were 81.7(77.7-86.0) Gy when irradiated under clamped hypoxia, 69.6 (66.8-72.5) Gy under air breathing condition,67.5(64.1-71.1) Gy with a single dose of GBE (100 mg/kg) given one hour before irradiation, and 62.2(59.1-65.5) Gy with two doses of GBE given at 25 hours and one hour before irradiation. The hypoxic cell fractions, estimated from TCD50/120's were 1.6% under air breathing ondition, 7.2% after single dose of GBE, and 2.7% after two doses of GBE. He results of 31P NMR spectroscopy were as follows. PCr/Pi ratio was 0.27 +/- 0.04 and 0.40 +/- before nd one hour after a single dose of GBE(p<0.01). These findings indicate that the metabolic status is slightly improved after a single dose and markedly after repeated administrations. CONCLUSION: GBE decreases the hypoxic cell fraction and improves the metabolic status of tumor, probably by increasing the blood flow and delivery of oxygen and nutrients, resulting in increased radiosensitivity of tumor.

Relationship between decrement of muscular pH and CO2 excess during incremental exercise / 体力科学

A study was conducted to investigate using <SUP>31</SUP>P NMR the relationship between the total excess volume of CO<SUB>2</SUB> output (CO<SUB>2</SUB> excess) due to bicarbonate buffering of lactic acid produced in exercise and the decrease of intracellular pH during incremental exercise. Five sprinters and 5 joggers performed incremental exercise to exhaustion on an bicycle ergometer. The values of CO<SUB>2</SUB> excess and CO<SUB>2</SUB> excess per body weight (CO<SUB>2</SUB> excess/W) were not different between the sprinters (2388±659m<I>l</I>, 36.7±8.5 m<I>l</I>·kg<SUP>-1</SUP>) and the joggers (2275±278m<I>l</I>, 40.0±6, 3m<I>l</I>·kg<SUP>-1</SUP>) . Below the ventilatory threshold (VT), from VT to the respiratory compensation point (RCP), and above RCP, the V<SUB>od2</SUB>-V<SUB>co2</SUB> slopes were not different between the sprinters and the joggers, respectively (0.95±0.05 vs 0.95±0.06, 1.21±0.11 vs 1.30±0.14, 1.69±0.24 vs 1.76±0.18) . However, the joggers showed significantly higher CO<SUB>2</SUB> excess/W per blood lactate accumulation (ΔLa) in exercise (CO<SUB>2</SUB> excess/W/ΔLa, 5.34±0.32m<I>l</I>·kg<SUP>-1</SUP>·mmol<SUP>-1</SUP>·<I>l</I><SUP>-1</SUP>) than the sprinters (4.50±0.14m<I>l</I>·kg<SUP>-1</SUP>·mmol<SUP>-1</SUP>·<I>l</I><SUP>-1</SUP>) . The decrement of intracellular pH during incremental exercise showed a tendency to be smaller in joggers (0.63±0.18 pH unit) than in sprinters (0.83±0.10 pH unit), although there was no significant difference between the two groups. The values of CO<SUB>2</SUB> excess/W/ΔLa were correlated with the decrease of intracellular pH (r=-0.792, p<0.01) . It is suggested that CO<SUB>2</SUB> excess/W/ΔLa reflects the efficiency of the bicarbonate buffering system, and could be an important factor influencing the decrease of intracellular pH due to lactate production.

Studies on muscle metabolism and cross-sectional area in the elite Japanese soccer players using NMR / 体力科学

We investigated the muscle energetics using <SUP>31</SUP>P nuclear magnetic resonance (<SUP>31</SUP>P NMR) spectroscopy, muscle cross-sectional area by magnetic resonance imaging (MRI), isokinetic strength, maximal anaerobic power and 40-sec maximal cycling test (40 seconds power) in All Japan soccer players (JPN: n=6), Olympic and Youth representatives (OL: n=6), and Japan Soccer League players (JSL: n=5) . There was no significant difference in muscle energy metabolism measured by <SUP>31</SUP>P NMR between the JPN and the OL or JSL players at rest, during exercise, or in the recovery period. The total muscle cross-sectional area was significantly larger in the JPN players than in the OL players at the upper (70%) and the middle (50%) parts of the thigh (p<0.05) and than in the JSL players in the upper (p<0.01), middle (p< 0.05), and lower (30%) parts (p<0.01) . The isokinetic strength in left leg extension at 180 deg/sec was significantly greater in the JPN players than in the OL players (p<0.05) . Muscle strength was also greater in extension of both legs at 450 deg/sec (left p<0.05, right p<0.01) in the JPN players than in the JSL players. The maximum anaerobic power was significantly greater in the JPN players than in the OL players (p<0.05) and the JSL players (p<0.05), and the anaerobic power per kilogram of body weight was significantly higher in the JPN players than in the JSL players (p<0.01) . There was no significant difference in the 40 seconds power among the three groups. These results suggest that the JPN players have greater muscle power than the OL or JSL players because of the differences in the muscle mass.

Magnetic resonance methods for studying intact spermatozoa.

Motility is used as a routine parameter for assessing spermatozoa activity. The quality rating techniques adopted are based on electron or optical microscopy. However, these methods depend on gross structural and dynamical features of sperm cells and do not provide information on metabolic activity of intact cells. Lately, biochemical assays have become popular. Such methods are cumbersome and destroy the samples. Magnetic resonance methods offer a non-invasive method for studies on intact sperms. We have investigated respiration, maturation and in vitro capacitation of sperms from human ejaculates and sperms extracted from goat reproductive organ using electron spin resonance spin labelling and [31P] nuclear magnetic resonance methods. These studies clearly establish the advantages of magnetic resonance in studies related to metabolic activity of sperms.

Nuclear magnetic resonance and thermal studies of drug doped dipalmitoyl phosphatidyl choline-H2O systems.

The influence of the sulfone drugs, diamino diphenyl sulfone and diamino monophenyl sulfone on the phase transitions and dynamics of dipalmitoyl phosphatidyl choline-H2O/D2O vesicles have been investigated using differential scanning calorimetry and nuclear magnetic resonance. Our results show that diamino diphenyl sulfone interacts quite strongly with the headgroups of dipalmitoyl phosphatidyl choline whereas the diamino monophenyl sulfone-dipalmitoyl phosphatidyl choline interaction is quite weak. This is attributed to the difference in the structure and hydrophobic character of the two drugs.

~31P-NMR STUDIES ON INTRACELLULAR pH AND ENERGY METABOLISM OF HEART, KIDNEY AND LIVER IN BURN SHOCK: AN ANIMAL EXPERIMENT / 第二军医大学学报

Cellular energy metabolism and intracellular pH of intact heart, kidney and liver of small animals were studied before and after burn with an effective technique of phosphorus-31 nuclear magnetic resonance (31P-NMR) spectroscopy. Advantages of this technique are that the measurement can be performed constantly without any complicated and destructive process, that it is possible to use this technique in clinical examination in the near future and that a lot of information can be obtained from only one spectrum.It was demonstrated that there were a short cellular energy source and a cellular acidosis in' heart, kidney and liver during burn shock. The high-energy phosphate compounds-lowered wavily but not straight, which could be divided into stress stage, compensation stage and decompensation stage. Intracellular pH decreased first in the heart, and then in the kidney and liver. In contrast to the results obtained by way of direct blood flow determination, the early and significant intracellular acidosis indicated the insufficiency of blood and oxygen supply in myocardium.

[31P] -Nuclear magnetic resonance spin lattice relaxation in lecithin reverse micelles.

[31P] -Nuclear magnetic resonance (NMR) spin lattice relaxation times (T1) have been measured for lecithin-nonpolar solvent-water as a function of added water for three solvents, namely, benzene, carbon tetrachloride and cyclohexane. In benzene and carbon tetrachloride systems, where spherical reverse micelles are formed, [31P]-NMR T1, values increase linearly with added water. However, in cyclohexane, the trends in the [31P]-T1 values indicate very different micellisation processes. Even at the lowest concentration of added water, the [31P]-T1 values in this solvent are substantially larger than the corresponding values in benzene and carbon tetrachloride, which is attributed to the intramolecular chlorinephosphate interaction being the weakest in cyclohexane. At a higher water content of six mols of water per mol of lecithin in cyclohexane solvent, the [31Ρ]-T1 values show a sharp decrease indicating a sudden change in the dynamics of the phosphate group, and this confirms the on set of 'reverse micelle-to-liquid crystalline' phase transition observed in this system by other spectroscopic and physical techniques.