Norman R. Joseph

Interaction of ions and connective tissue.

The interaction of ions with tissues was studied by measuring liquid junction potentials between tissues and 0.15 M KCl, and LiCl, or 0.075 M CaCl2 and MgCl2, as well as with one tenth isotonic NaCl. For baseline values, 0.15 M NaCl was used. In this way a series of substitution and dilution potentials was established. As a connective tissue which varies in physicochemical state, use was made of the symphysis pubis of normal and castrate guinea pigs, and of guinea pigs in various stages of pregnancy. The former have tight, unrelaxed symphyses, while the latter show varying grades of relaxation. Experimentally, relaxation was also induced by the use of estrogens and relaxin in castrate guinea pigs. Unrelaxed symphyses showed high positive dilution potentials (+20 to + 30 mv), while highly relaxed symphyses showed zero or negative dilution potentials, approaching in some cases values calculated for aqueous salt junctions (—12.3 mv). These results are interpreted on the basis of a high concentration of negatively charged immobile colloid in tight connective tissue; following induction of the physiological change of relaxation, the potentials indicate low densities of immobile charged colloid. An estimate of 1250 for the average base binding equivalent weight of tissue colloids indicates a magnitude characteristic of mucopolysaccharides or mucoproteins. Evidence from other work indicates that relaxation in the symphosis is accompanied by a disaggregation (depolymerization) of components of ground substance, and by an increase in water soluble fractions. In relaxed symphyses, where colloid density is low, mobility data indicate that the cations approach their behaviour in water. In tight symphyses, selective effects appear, related to the high concentrations of immobile charge. Potassium in particular showed a marked decrease of mobility to approximately one-half its value in water. Effects with other ions were much smaller. Thus connective tissue in a state of high aggregation appears to act selectively as an ion-exchange resin for potassium; with breakdown of aggregates and uptake of water, selectivity is lost. From the NaCl dilution potentials, concentrations of immobile charges were estimated. Values ranged from 0.20 equivalents per liter in the tight symphysis to 0.05 equivalents per liter or less in the relaxed state. Values of this order of magnitude have been calculated from independent data.

A pH Calculator Based on Linear Transformations of the Henderson-Hasselbalch Equation

The four classical methods of determining the mass of the moon are noted, and a new use of an artificial earth satellite is proposed. The procedure, based on Keplers law, is outlined, but at present the uncertainties in the observed data preclude an improved estimate of the lunar mass.

Effects of hyaluronidase and cortisone on connective tissue studied electrometrically.

Summary Reversal of hyaluronidase effects on concentration of negatively charged colloids in the dermis of normal and cortisone treated rabbits was studied by serial measurement of liquid junction potentials. In normal animals, hyaluronidase lowers negative charge density in the tissues; recovery is half completed in about 4 hours. In animals treated with cortisone initial charge density is lower than in normal animals. After hyaluronidase is injected into the dermis, the lowest levels are reached. Half recovery, however, occurs in 2 1/2 hours. Serial electrometric measurements following hyaluronidase injection are suggested as a means of studying hormone and drug effects, and disease states in connective tissue.

The pH of the synovial fluid in the anaesthetized dog under treatment with metrazol or insulin.

This paper reports the results of alterations in the pH of synovial fluid and of blood of dogs anaesthetized with nembutal, in response to agents producing extreme muscle activity. The intravenous administration of metrazol, in doses producing convulsions, resulted in a more pronounced decrease in the pH of synovial fluid than in that of blood. This difference was progressively developed to a maximum stage somewhat later than in blood. The injection of insulin produced similar, but less pronounced, results, although the graphs were less smooth and regular and there was better correlation between the alterations of pH in the two fluids.

Effects of Temperature and Anions on Titration Curves of Frog Muscle

Titration curves of frog muscle at 2 �C and 25 �C were determined in vivo. Lowered temperature decreases respiration without change of colloidal charge or of ion distribution as estimated from charge. Anions which are inhibitors or metabolites combine with muscle colloids, changing the distribution of other ainions and cations.

Red Cell Charge as Affected by Low Viscosity Dextran.

Summary The effects of trauma and LVD on red cell charge were studied electrometri-cally using normal subjects, post-surgical and shock patients. The highest levels of negative colloidal charge were found in a group of 11 shock patients, all characterized by cellular aggregation and microcirculatory derangements. The administration of LVD resulted in increases of negative colloidal charge in all patients. The greatest increases (30%) were found in normal patients. LVD infusion produced a marked improvement in the circulatory status of shock patients, but the negative colloidal charge was increased only by about 5%. The results show that the effect of LVD on agglutination of erythro-cytes depends not only on the magnitude of the surface charge, but also on the physico-chemical nature of the surface which is formed.