Research Methods In Neurochemistry

Section I Ultrastructure and Fragmentation of Neural Tissue.- 1 Bulk Separation of Neuronal Cell Bodies and Glial Cells in the Absence of Added Digestive Enzymes.- I. Introduction.- II. Bulk Isolation Procedures Requiring No Added Digestive Enzyme(s).- A. The Procedure Developed in the Authors' Laboratory.- B. The Procedure of Nagata et al. (1971).- C. The Procedure of Iqbal and Tellez-Nagel (1972).- D. The Procedure of Jones et al. (1971).- III. General Procedural Comments.- IV. Cell Yield and Biochemical Characterization.- V. Applications in Cellular Neurochemistry.- A. Centrifugal Fractiona.

On picking up this first volume of a new series of books the reader may ask the two questions: (a) why research methods? and (b) why in neurochem istry? The answers to these questions are easy - they more than justify the volumes to come and show the strong need for their existence. It is customary to think of methods as a necessary but unexciting means to an end - to relegate advances in methodology to a minor role in the creative, original portion of advances in science. This is not the case; the pace-setting function of methodology is well illustrated in most areas of neurobiology. To formulate our questions to Nature (which is the essence of experimental design), methodology is needed; to get answers to our ques tions we have to devise yet new methods. The chapters of the present volume fully illustrate how the development of a new method can cut a new path how it can open new fields, just as the microscope founded histology. Heter ogeneity of structures presents a formidable challenge for methodology in the nervous system, yet methods for separating the structures are essential if we ever want to decipher the enigma of functional contribution of the ele ments to the whole. The problem is not only physical separation-clearly methods are essential to study complex structures in situ.

With the continued rapid expansion of neurochemical research, there has been no shortage of new developments in methodology for this third volume of Research Methods in Neurochemistry. As in previous volumes we have again tried to provide some balance in the subjects represented. The wisdom of this policy may be questioned since it can lead to delay in publica tion, but there are many approaches to the chemical study of the nervous system and a methods book needs to stand on its own as well as be part of a series. In one respect, however, the present volume departs from this policy, in that we have included two chapters on micromethods for analyzing amines and amino acids, both giving special emphasis to dansylation techniques. These chapters are complementary and we feel justified in publishing them in one volume in view of the importance of such micromethods for the study of neural systems. At the other end of the scale, particular attention may be drawn to the chapter by D. D. Gilboe and colleagues describing their remarkable procedures for studying metabolism in the isolated canine brain. We were fortunate also in persuading S. S. Oja to extend the general prin ciples of transport systems he described in Volume 2 to amino acids in brain slices. In addition, there are the usual chapters on components of neural tissues, which once again we have found convenient to divide into enzymes, macromolecules, and other constituents.

The fourth volume of Research Methods in Neurochemistry includes chapters on different aspects of topics touched on in previous volumes and develops a number of new themes as well. The bias, though not entirely intended, is directed toward studies of macromolecules, both at the meta bolic level in relation to protein synthesis and at the structural level in rela tion to specific proteins and lipids. The new departures concern subjects in Section I with marked applied bias: biochemical studies of nervous system tumors and of the cerebrospinal fluid, both of which we hope will be of value to clinical as well as basic scientists. Biogenic amines and the enzymes involved in their metabolism figure again in Section II, where the powerful tool of mass spectrometry receives further treatment in relation to the analysis of dansyl derivatives of trace amines in the brain. Once again we remain grateful to the individual authors, both for their contributions and patience, and to Plenum Press for their continued interest and cooperation. Thanks are also due to colleagues and friends for their comments and criticisms on the series as a whole; suggestions for future volumes will always be welcome and should be sent to one of the editors. Richard Rodnight, London Neville Marks, New York March 1978 ix Contents Section I PROPERTIES OF INTACT NEURAL TISSUES Chapter 1 Biochemical Study of Tumors of the Nervous System. . . . . . . . . . . . . . . . 3 Norman Allen I. Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 II. Human Brain Tumors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 A. Autopsy Specimens. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

This fifth volume of Research Methods in Neurochemistry represents a milestone in that it marks almost a decade since the inception of the series. Over these ten years there has been an almost exponential growth in neuro chemistry accompanied by numerous technical developments. This is the justification for our series; inevitably we have only been able to cover a frac tion of the methodological innovations of the last decade, but we have tried as much as possible to create a balance between the different approaches and philosophies in the study of the chemical basis of brain function. Thus our original format of grouping chapters under various headings-for instance, studies in intact tissues as distinct from studies describing constituents and isolated enzymes-appears to be justified. Studies on whole animals or tissues retaining cellular organization are vital in providing insights into the neurochemical mechanism underlying functional processes; at the same time, the eventual understanding of function can only be attained on the basis of knowledge of the molecular architecture of the tissue. In the present volume, Oldendorfs chapter on the transport of radiolabeled metabolites across the blood-brain barrier illustrates one side of this equation, whereas Poduslo's chapter on the separation of oligo dendroglia! cells provides new information on the role of these cells in myelogenesis and the distinctive chemical composition of glia as compared to neurons.