The theory of chemical or neurohumoral mode of nerve transmission is generally accepted today. According to this concept, the arrival of an impulse at the nerve ending in ganglia or at a synapse with a muscle cell results in the release of a chemical substance, called a "transmitter". [...]

The theory of synaptic transmission in the nervous system describes the propagation of nerve impulses through a network of "neurones". "Neurones" was used by Waldeyer (1891) to describe the nerve cells which includes the nucleated cell body as weil as ali of its processes. Nerve cells are separated from but intermingled with its neighbors. There is no continuity between adjacent processes as was previously believed. lnstead, a synapse (Sherrington, 1897) was thought to be present at the point of contact between any two links in the chain of cells (Schafer, 1900). [...]

The ability of sectioned rat adrenals to respond to ACTH in vitro has been demonstrated (1,2,3) but a detailed time study to show the degree and maintenance of this response over a prolonged period has not been carried out. The first aim of this study was to investigate the conditions necessary for the maintenance of increased corticosteroidogenesis, in response to ACTH, over an incubation period of 10 hours. [...]

It is now generally accepted that the clinical efficacy of the preserved blood specimens is determined by the metabolic status of the erythrocytes. The changes that occur in the metabolic potential of the cells during the storage period influence greatly the viability of the cells, that is, the ability of the cells to remain in the circulation on transfusion. [...]

The investigations reported in this thesis are concerned with the synthesis of ribonucleic acid in rat brain cortex slices. In an attempt to correlate the metabolism of RNA in vitro with the functioning of the brain in situ, brain slices were stimulated by changes in the concentrations of cations in the incubation medium as well as by the application of electrical pulses. [...]

It is only in the last two decades that the metabolic origin and function of phospholipids have lost some of their mystery. Thudichum (1, 2) reported in the 1880's the occurrence of lipid-associated phosphorus, and later studies only succeeded in establishing the general importance of this class of lipids as constituents of tissues. [...]

Todd (1) has stated in a review on cancer research that "everything comes back finally to nucleic acids". This aspect of tumour cell metabolism has formed the major part of this thesis. [...]

A distinctive feature of the chemical composition of the central nervous system is its high content of glycosphingolipids. The simpler members of this group, cerebroside, and cerebroside sulphate are found predominantly in the myelin sheath, and thus they may occur in greater amounts in glial cell membranes than in neuronal cell membranes. [...]

It is undoubtedly of considerable significance that purines occur in every living source which has been examined. The purines are integral parts not only of all the nucleic acids studied, whether of true cellular origin or in the less specialized structures, the viruses, but they are also essential constituents of coenzymes, adenosine-5' -triphosphate (ATP), etc. [...]

The purpose of this investigation was to gain further insight into the mechanisms governing the formation and release of ACTH by the pituitary gland. [...]