THE GLUTAMATE AND GLUTAMINE CONTENT OF RAT BRAIN AFTER PORTOCAVAL ANASTOMOSIS

Abstract— Rats have been subjected to portocaval anastomosis and the ammonium ion in plasma and the glutamate and glutamine levels in plasma, red cells and brain have been estimated up to 6 weeks after operation. The glutamine, but not the glutamate, levels in brain were consistently raised, being about 2.5 times greater than normal and the level can be correlated with the level of plasma ammonium ion. Consideration is given to the possibility that the glutamine may be in the greatly enlarged neuroglial compartment in this abnormal metabolic state.     

The effect of phagocytosis of Candida albicans blastospores on alkaline phosphatase levels in rat polymorphonuclear leucocytes

Summary The phagocytic function of young polymorphonuclear leucocytes with high levels of leucocyte alkaline phosphatase, which are present in the peripheral blood during an inflammatory response, was compared with that of normal polymorphonuclear leucocytes.Candida albicans blastospores were used as phagocytic targets. The phagocytic index of polymorphonuclear leucocytes with low levels of leucocyte alkaline phosphatase was higher than that of cells with high levels of enzyme.Monitoring of leucocyte alkaline phosphatase levels with increasing times of incubation of leucocytes with the blastospores showed a progressive decline in the level of the enzyme. Thus loss of the enzyme is linked to the phagocytic function, although the mechanism of this dynamic process is unclear.     

Structure, regulatory polymorphisms, and allelic hypervariability regions in murine I-A alpha

Class II major histocompatibility complex (MHC) molecules, the Ia antigens, are intimately involved in regulating the intensity and specificity of the cellular and humoral responses to T cell-dependent antigens. One approach to understanding the mechanism of this regulation is to analyze the structure and allelic polymorphism of Ia molecules. In addition there are regulatory polymorphisms in the expression of the I-E alpha and I-E beta class II MHC polypeptide chains. Analysis of the cDNA sequence indicates that I-A and I-E alpha chains are similar with short stretches of homology and other regions of nonhomology. Analysis of Northern blots of mRNA indicates that at least three separate types of regulatory polymorphisms result in failure of expression of I-E alpha. Comparison of allelic sequences of six alleles of the I-A alpha chain shows that almost all of the allelic polymorphism is in the first domain and that within the first domain it is clustered in three allelic hypervariable regions within the first domain of I-A alpha. The structural and functional implications of these findings are discussed.     

The effects of suspending medium viscosity on erythrocyte deformation and haemolysis in vitro

Fresh adult human erythrocytes were suspended in isotonic pH adjusted solutions containing various concentrations of Dextran T.500. The cells were subjected to uniform hydrodynamic shear stress in a Ferranti Shirley Cone and Plate Viscosimeter. The amount of lysis incurred at any given combination of explosure parameters was markedly affected by the viscosity of the suspending medium. Optical diffraction patterns obtained whilst the cells were undergoing shear demonstrated that cellular deformation was also a function of viscosity. Consequently, the distorted shape of the stressed cell must play a crucial role in the haemolytic process.     

Electron transfer in biology

Table VII presents a list of the topics I have discussed. Underlying biological electron transfer which employs metal ions overwhelmingly is the intimacy of the interaction between metal ion properties and protein properties. Attacking the problems is attacking a cornerstone of life - bioenergetics. It is appropriate that this is the Heyrovsky Memorial Lecture since he devised the polarograph which is a device for coupling electrolytes (protons) in solution with electrons in metal atoms.