Solubility of various inert gases in rat skeletal muscle

For the determination of solubility coefficients, isolated rat abdominal muscles were equilibrated at 37 degrees C with various inert gases saturated with water vapor. After rapid transfer into a closed chamber containing room air the amount of gas extracted from the sample by diffusion was measured by gas chromatography. Corrections for unextracted gas and for gas lost during the transfer of the sample were applied. The following mean values for the solubility coefficients, in mumol-1(-1)-torr(-1), were found: chloro-difluoro-methane (Freon 22), 56.0; acetylene, 55.5; nitrous oxide, 27.7; methane, 2.42; hydrogen, 1.13; helium, 0.608; sulfur hexafluoride, 0.559. The relationships between solubility in tissue, in water and in olive oil are discussed.

Diffusivity of various inert gases in rat skeletal muscle

Krogh’s diffusion constant (K) was determined for various inert gases in isolated rat abdominal muscle at 37 degrees C by measuring the amount of gas diffusing per unit time and partial pressure difference through a portion of the muscle of known surface area and thickness. The following mean values for K, in 10(-9) mmol-min-1-cm-1-torr-1, were obtained: C2H2, 42.2; N2O, 20.0; CHClF2, 18.8; H2, 1.67; He, 1.42; CH4, 1.27; SF6, 0.081. From Krogh’s diffusion constant, the diffusion coefficient (D) was calculated using the solubility coefficient determined previously in the same preparation. The D values thus obtained were found to be about half the D values in water at 37 degrees C. Model calculations show that for gases with high lipid/water partition coefficient, D in tissues containing lipid is underestimated by this method. Graham’s law (inverse proportionality between D and square root of molecular mass) was found to represent a useful approximation for these gases. A better correlation, however, was obtained between D and the molecular diameter.

Hyperbaric hydrogen therapy: A possible treatment for cancer

Hairless albino mice with squamous cell carcinoma were exposed to a mixture of 2.5 percent oxygen and 97.5 percent hydrogen at a total pressure of 8 atmospheres for periods up to 2 weeks in order to see if a free radical decay catalyzer, such as hydrogen, would cause a regression of the skin tumors. Marked aggression of the tumors was found, leading to the possibility that hyperbaric hydrogen therapy might also prove to be of significance in the treatment of other types of cancer.