Microprobe analysis of element distribution in rabbit and dog erythrocytes as examples of "high" and "low" potassium cells.

The concentrations of Na, Mg, P, S, Cl, K and Fe were determined by microprobe in near 100% hematocrit suspensions of rabbit and dog erythrocytes prepared by freezing and drying. These cells are representative, respectively, of "high" potassium, "low" sodium, and "high" sodium, "low" potassium cells. Water contents of the cells were the same, as were, approximately, the levels of Cl, S and Fe. Rabbit P was nearly double that of the dog. For the rabbit, the cell Na/K ratio was 0.21 and for the dog 15.4, illustrating the major diffusible electrolyte difference between these two types of cell. The rabbit erythrocytes showed an apparent negative immobile charge density of 95 meq/kg of cell water and the dog 56 meq/kg cell water, a distinct difference. Serum electrolytes in the two species are exactly comparable (Standard Tables). Ionic distribution in these cell types was treated by the Gibbs-Duhem equation representing two heterogeneous systems in thermodynamic equilibrium with the blood serum. Factors to be considered are: (1) the composition of the erythrocyte and its net immobile charge; (2) the physicochemical properties of the individual ions (charge, ionic radius, hydration energy, standard chemical potential); (3) the dielectric constant of the dispersion medium (in this case, water); and (4) the binding constants of the ions. The hypothesis of "active transport" (the sodium-potassium pump) is specifically rejected as an explanation of ionic differences.

Radiological evaluation of bone status in the jaw and in the vertebral column in a group of women.

Vertebral bone mineral content was determined in a group of 56 women, ages 30-62. These measurements were compared with the status of supporting bone in the jaws (alveolar, molar and bicuspid) and with gingival health. There was a significant decline in vertebral bone mineral content from the pre- to post-menopausal group. Molar and bicuspid measurements were highly correlated. There was some association between lumbar bone mineral content and molar bone status for postmenopausal women. For postmenopausal women, the cases of greatest percent bone loss in alveolar crest were associated with lower lumbar bone mineral content. Gingival health did not confound the bone status measurements. The 56 subjects did not exhibit the degree of reduction in bone density that is observed in the general population. Further investigation using these radiographic techniques may reveal a link between substantial bone loss in the jaw and moderate to severe bone loss in the lumbar vertebrae.

Microprobe analysis of element distribution in bovine extracellular matrices and muscle.

The concentrations of some essential elements, Na, K, P, S and Cl were determined by microprobe analysis in bovine extracellular matrices of cartilage, tendon and elastic tissue (ligamentum nuchae) and in muscle cells. The values for the different tissues were compared and related to the blood electrolyte concentrations. Among the connective tissues the highest Na and lowest Cl values were found for cartilage which bears a high negative charge. The lowest concentrations of these elements occurred in elastic tissue which is relatively non-polar. In the three extracellular matrices sodium levels exceeded potassium. In myofibers potassium was the major cation at 30 times the blood value and about 3 times the concentration of sodium. Chlorine values were around 0.4 that of blood. Sulfur and phosphorus are components of the tissue macromolecules. The negative charge on the extracellular matrices is a function of carboxyl and sulfate radicals. In the myofiber this property is largely attributable to carboxyl and phosphate groups. Differences in potassium-sodium distribution in cells and extracellular matrices are attributed partly to the microtrabecular lattice and to the ordered state of cell water. In general the element concentrations and selective distribution can be related to the chemical composition and organization of the tissue, the net immobile charge, the nature of the dispersion medium (water) and changes in its dielectric constant, and to the physico-chemical properties of the individual ions.

The effect of fatigue on essential element distribution in the rabbit masseter.

The rabbit masseter is composed of mainly fast fatiguable type IIB fibers which give a positive mATPase reaction at pH 9.3. To study the effect of fatigue on the distribution of some crucial elements, the masseter was stimulated electrically for 45 minutes. The contralateral muscle served as a control. Control and experimental tissues were rapidly excised, and frozen in isopentane cooled to -150 degrees C in liquid nitrogen. Sections were cut in a cryostat and prepared by freeze-drying. Water content of fatigued muscle was significantly higher than controls: 79.3% versus 77.3%. The fatigued state was verified by glycogen depletion viewed in PAS-stained sections. Ice crystal artifacts were more prominent in stimulated muscle, suggesting cytoplasmic edema and/or a change in water state. Element analysis of myofibers, using an scanning electron microscope equipped with a computer assisted energy dispersive X-ray spectrometer was performed at 15 kV for 100 seconds. Counts were recorded for Na, Mg, P, S, Cl, K and Ca (Mg and Ca counts were too low to evaluate). Counts were converted to concentrations using a gelatin element standard. The most striking finding in fatigued muscle was a decrease in K concentration (33%) and an increase in Na (100%) and Cl (75%). P and S values were slightly lower. An interpretation of these findings is made in relation to a) changes in water structure and b) conformational changes in myofibril macromolecules.

Quantitation of isotype specific Haemophilus influenzae antibody in serum and saliva of normal subjects and chronic bronchitics.

An immunoglobulin isotype specific radioimmunoassay procedure has been developed to assess the antibody response to Haemophilus influenzae somatic antigens in serum and mucosal secretions. This assay was reproducible (between assay CV% 13.9; within assay CV% 4.5 IgG, 3.9 IgA, 3.0 IgM) and specific for H1/H2 antigens. Different patterns of antibody were observed in healthy children (aged 5-10 years), adults and patients with chronic bronchitis. In serum, 20% of chronic bronchitics had antibody levels greater than those observed in healthy adults. In saliva, the proportion of chronic bronchitic patients with high levels (greater than 12% binding) of IgG specific antibody was significantly greater (P less than 0.05) than in healthy adults or children. The proportion of children and chronic bronchitics which had antibody levels of up to 4% binding was significantly greater (P less than 0.05) than that observed in healthy adults. A similar pattern was observed for IgM specific antibody. The occurrence of IgA specific antibody in the saliva in children and chronic bronchitics was consistently greater than that observed in adults for all levels of antibody (P less than 0.05). Chronic bronchitics with high levels of antibody had greater infection and mortality rates.

Changes in distribution of some crucial elements in masseter myofibers following surgically induced trauma.

Experimentally induced surgical trauma of the masseter muscle in rats led to changes in the distribution of some crucial intracellular elements as determined by microprobe analysis. Sulfur, phosphorus, and potassium values were lowered while sodium and chlorine levels were elevated. These changes were accompanied by increased formation of ice crystal artifacts in myofibers. The findings suggest that trauma causes alterations in cytoplasmic macromolecules and in the state of water in the cells. The method of analysis provides a means for the further evaluation of antiinflammatory drugs.

Mineralization of developing teeth.

The distribution of some essential elements and mainly Ca & P in mineralizing matrices of enamel, dentine and predentine and in contiguous cellular strata of developing mouse molars was studied by electron probe analysis, supplemented by polarization microscopy. Distribution gradients for Ca, P, & Ca/P were noted in the matrices. In the early stages of mineralization of enamel and dentine (predentine) Ca/P ratios were low suggesting the presence of either amorphous forms of calcium phosphate or protein bound calcium. Calcium concentrations in odontoblast and ameloblast strata were notable. Elevated values were recorded in the ameloblast layer of the most mature stage (14 days). Sulfur concentration in early enamel exceeds by tenfold that of mature enamel largely due to loss of methionine. The substantial levels of sulfur in predentine are barely detectable in dentine probably due to the loss of sulfated glycosaminoglycans. The mineralization of the negatively charged matrices of enamel and dentine is associated with the loss of water, changes in composition and in the state of aggregation. The accumulation of calcium in crystalline and other forms can be explained by the conditions of the Gibbs-Donnan equilibrium.

Effect of indomethacin on postsurgical edema in rats.

The effectiveness of intramuscular indomethacin was compared with that of hydrocortisone succinate for the control of edema resulting from experimentally induced surgical trauma in rats. Both drugs produced a significant reduction in tissue water, but no difference could be detected between the effects of the two drugs. These findings indicate the advisability of clinical trials of indomethacin in the control of postsurgical swelling and pain.

Microprobe analysis of human masseter muscle biopsies.

Biopsies of the human masseter muscle were made using an intraoral approach. Sections were cut in a cryostat and freeze-dried. Using the myosin ATPase method at pH 9.3 the recognized heterogeneity of the muscle with respect to type I and type II fibers was confirmed. Sections were examined in an SEM by the method of energy dispersive X-ray analysis using a computer assisted semi-quantitative method (bulk analysis-thick sections) to determine the distribution of Na, P, S, Cl and K and their relative masses. Element concentrations in descending order were K, S, P, Na and Cl. Some element ratios were compared with results in the literature for other muscle (biochemical and microprobe analysis) and found to be generally in reasonable agreement. The results form a basis for the study of a prominent and accessible masticatory muscle in altered states.

Microprobe analysis of calcifying matrices and formative cells in developing mouse molars.

The distribution of Calcium and Phosphorus and of Na, K, S and Cl was studied in the mineralizing matrices and strata of ameloblasts and odontoblasts in developing mouse molars (5-14 days). Sections cut in a cryostat were prepared by freeze-drying and examined in an SEM by the method of energy dispersive x-ray analysis. In enamel a gradient of mineralization was observed with respect to age and topography. Progesssive loss of sulfur was also demonstrated. Less striking mineralization gradients were found in dentin. Predentin accumulated Ca at a concentration about 2% that of dentin and the Ca/P ratio was lower than that for apatite. Significant concentrations of calcium were localized in ameloblast and odontoblast strata. The concentration increased five-fold in ameloblasts as the cells matured and enamel mineralization entered the final phases, levels in odontoblasts remained stable. With age in both cellular strata, potassium counts decreased. In maturing ameloblasts the concentrations of sodium and chloride rose.