Metabolic Turnover In The Nervous System

Volume V deals with the problems of turnover in the nervous system. "Turnover" is defined in different ways, and the term is used in different contexts. It is used rather broadly in the present volume, and intentionally so. The turnover of macromolecules is only one aspect; here "turnover" in dicates the simultaneous and coordinated formation and breakdown of macromolecular species. The complexities of cerebral protein turnover are shown in aseparate chapter dealing with the synthesis ofproteins, in another on breakdown, and in still another on the relationship ofthese two (showing how the two halves of turnover are controlled). The fact that most likely the two halves of protein turnover, synthesis and breakdown, are separated spatially and the mechanisms involved are different further emphasizes the complexity of macromolecular turnover. "Turnover" is used in a different context when the turnover of a cycle is discussed; but he re again a number of complex metabolic reactions have to be interrelated and controlled; some such cycles are discussed briefly in this volume, additional cycles have been discussed with metabolism, and some cycles still await elucidation or discovery.

This volume is concerned with metabolic reactions occurring in the nervous system. Some time ago, it was thought that since most of the intermediary metabolism that can be observed in the brain is not specific to this organ, there is little justification in studying neural metabolism as such. Later it was realized that for an understanding of neural functions, the understanding of metabolism in the brain and its alterations is essential. All aspects of the metabolism of a substrate in brain, or all metabolic reactions of the nervous system, could not be included in this volume; some will be dealt with in other volumes (such as the ones covering metabolic turn over, alterations of metabolism, or pathology). Review of the aspects covered here clearly shows that the study of metabolic reactions in the nervous system is a very active field, producing important results. As in so many areas of research, as we learn more, new aspects become known, new questions emerge, and we see that in solving some problems we open areas with many additional problems to solve. But the accomplishments to date are impressive and indicate further important advances in the future. Brain metabolism is more active, more plastic, and more comprehensive than previously estimated. It is an essential part of brain function, and with its alteration, brain function will be altered. This shows the importance of more knowledge in this area. It is hoped that this volume will be of assistance in such further studies.

Metabolism of the Nervous System contains the proceedings of the 2nd International Neurochemical Symposium, held at Aarhus, Denmark, in July 1956. The book discusses the molecular structure and morphology of the adult nervous tissue; the chemical composition and cytochemical localization of adult nervous tissue; and the permeability and blood-brain barrier. The text also describes topics on electrolytes and nervous conduction; the metabolism of isolated nerve and ganglion; and the metabolism of the brain in vivo. The metabolism of brain tissue preparations in vitro; energy metabolism and coenzymes in relation to the nervous system; and lipid and fatty acid metabolism are also considered. The book further tackles nucleic acid metabolism; protein and amino acid metabolism; and cholinergic and non-cholinergic transmission. The text also discusses other pharmacologically active compounds related to the adult nervous tissue.