Neuroscience Vol. 40, No. 1, pp. 295-296, Printed in Great Britain
1991
0306-4522/91 $3.00 + 0.00 Pergamon Press plc
BOOK
REVIEWS
Neuroanatomical Tract-tracing Methoda 2. Recent Progress. Edited by L. HEXMRR and L. WBORSZKY.Plenum Press, New York (1989) 408 pp. Price $69.50.
logically characterized neurons (Chapter 7). Tam& Freund and Peter Somogyi together have written Chapters 8 and 9, describing how synaptic relations can be clarified with the combination of Golgi-impregnation or HRP-filling with immunocytochemical and electrophysiological methods. The power of this approach is illustrated by their examples where “-&ctrophysiological recording showed the functional type of the tierents, electron microscopy identified their target cells, and immunocytochemistry revealed the putative transmitter of the latter”. The time and patience needed for these kinds of studies should not be overlooked; however, neither should the need for a critical interpretation of the results as emphasized by the authors. Chapter 10, written by Bibie Chronwall and others, describes in situ hybridization combined with retrograde fluorescent tract tracing, while Mikl6s Palkovits in the next chapter deals with “Microdissection in combination with biochemical microassays as a tool in tract tracing”. The anatomical localization of receptors by autoradiography is described by William Geary and Frederick Wooten in Chapter 12. They emphasize, among other things, that we still do not understand the significance of anatomical “mismatches” between distribution of receptors and their specific ligands, and that “Clearly, in some instances, the anatomic distribution of a receptor does not appear to describe a biochemically specific functional system”. The final chapter by Michael Shipley and others gives a well-written and practical introduction to image processing and image analysis; concepts the authors emphasize should not be confused. They also exemplify the old truth that “-the biological question should motivate the techniques used and not the other way around”. These days we may need to remind ourselves of this from time to time, particularly when faced with the possibilities offered by computer technology. The book contains a wealth of useful information. Each chapter is organized in a standard manner with, for example, separate sections dealing with advantages and limitations. Also, there are detailed protocols at the end of each chapter. References are listed at the end of each chapter, apparently up to 1988 for most chapters. Even in these days of rapidly appearing new methods and improvements of the old, this book should continue to be a useful source of information, and deserves to be available in all laboratories applying or considering to apply neuroanatomical methods.
When accepting this book for review I was not aware of it being dedicated to Walle Nauta, Jdnos Szentigothai and my late father, Alf Brodal. Although thus possibly not being totally unbiased, I see the book as a timely and proper tribute to these three pioneers of modem, functionally oriented neuroanatomy. The content of the book also serves to emphasize that neuroanatomy is, perhaps more than ever, a thriving and important part of the neurosciences. The previous volume, published in 1981, had a more limited scope, and so much has happened since then that an updated and expanded treatment is most appropriate. Throughout the volume one also gets timely reminders that there are no short-cuts to quality. The need for intimate knowledge of the methods used to interpret the results properly is evident from most chapters. Most contributions have in common the combination of modem tract-tracing methods with other means of characterizing neural tissue, and thus the book also serves to highlight the gradual disappearance of borders between traditional neuroanatomy and other approaches to the study of the nervous system. Enrico Mugnaini states, in an introductory chapter, that “In a sense, this book thus constitutes a guideline for a marriage of neuroanatomy and neurochemistry”. Chapter 2, written by Lana Skirboll and others, deals with the combination of fluorescent tracers and immunohistochemistry, whereas in Chapter 3 the PHA-L tracing method is described in detail by Charles Gerfen and others. This method is further treated, together with HRP, by L&lo aborszky and Lennart Heimer in Chapter 4 called, “Combinations of tracer techniques, especially HRP and PHA-L, with transmitter identification for correlated light and electron microscopic studies”. Chapter 5, by Virgiiia Pickel and Teresa Milner. further elucidates the ultrastructural identification of’ retrogradely labelled neurons and transmitter identification by way of autoradiography an9 peroxidase labelling. Pre-embedding double immunostaining is dealt with in Chapter 6 by Csaba Leranth and Virginia Pickel. Although not given a separate chapter, post-embedding immunocytochemistry is treated in other chapters (8 and 9). Stephen Kitai and coworkers detail their experience with intracellular labelling and immunocytochemistry of physio-
P. BRODAL
The NMDA Receptor. Edited by J. C. WATKINSand G. L. ~OLLINRIDGE. Oxford University Press, New York (1990) 242 pp. U5.00. We are becoming familiar with the promiscuity of neurotransmitters and their receptors. Put them together and several more receptor subtypes rapidly appear. These days, few transmitter candidates seem satisfied with a single receptor, so it was inevitable that sooner or later entire symposia would be devoted to single subtypes of receptors. This book is the proceedings of one such symposium, held
at the University of Bristol in association with a meeting of the British Pharmacological Society in April 1989. Its subject is the receptor for excitatory amino acids which has been characterized by its high atlinity for the synthetic amino acid-N-methyl+aspartaartate (NMDA). If ever a receptor deserved singling out for special attention it is the NMDA receptor. The exponential increase in research into this membrane recognition site in the last 15 years has been phenomenal. For this reason, of course, there is much new information which has appeared since the symposium which is not included, but due to its surprisingly rapid appearance,
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Book Reviews
the book does not suffer greatly from this. Although catchy, the title does not really do the book justice. This book is more than just information about the NMDA receptor per se.It is a reasonably detailed examination of the pharmacological and biophysical characteristics of the receptor and its possible roles in physiological and pathological processes in the central nervous system. In addition, of necessity, for comparative purposes it includes a considerable amount of up-to-date information on the non-NMDA (AMPA, kainate, metabotropic) receptors. The authors are leading experts in their particular fields who have been, and still are at the forefront of excitatory amino acid research. The meeting was structured to provide a logical progression from the history of the development of the NMDA receptor concept through to the characteristics of the receptor site (properties of antagonists, distribution, pharmacological responses), its physiological roles in central processes (synaptic pathways, long term potentiation, learning and memory, developmental plasticity) leading to involvement in disease states (epilepsy, neurodegeneration and antagonists as drugs). This order is maintained in the book and makes for easy reading. Nevertheless, for anyone not familiar with the field there is no real requirement to proceed through each chapter in order to be conversant with the next. Nearly all chapters are readable in their own right, with the authors providing a fairly detailed overview of their particular field before concentrating on their own research. There are excellent reviews included in many of the chapters (e.g. those by Watkins, Davies, Dale, Garthwaite and Herrling), and the final chapter by Watkins and Collinridge is useful in drawing attention to some topics not covered. There is some overlap between chapters, but this is inevitable and acceptable. Generally, there is a determined effort to interpret the experimental findings in terms of the overall physiology of excitatory amino acid transmission. Many chapters end by posing questions as to the
whys and wherefores of the NMDA receptor and such speculation is refreshing to read. While the difficulties of reproducing the audience discussion which takes place at symposia is acknowledged, it would have been nice to SW this attempted. My criticisms of the book are few. Personally, 1 would like to have seen a chapter dealing more generally with NMDA receptor-mediated transmission in areas of the cortex (the contribution by Artola and Singer being devoted to plasticity in the visual cortex) since a great deal of research has been, and is being done on this topic. A specific criticism which I would level at the scientific content is a rather misleading notion which crops up in several chapters. This is the suggestion that NMDA receptors are essentially blocked at resting potential and that NMDA-mediated depolarization is dependant on prior non-NMDA-mediated perturbation of the resting potential and/or requires special circumstances such as blockade of synaptic inhibition to be detected. While this may be the case at some sites, it is certainly not true for all and this could be a source of confusion for the reader unfamiliar with the field. This point is raised and adequately refuted in the chapter by Lodge et al. A criticism concerning the style of the book concerns the dreadful practice of listing references in non-alphabetical order and without titles. In general, the book provides a reasonably comprehensive account of the current status of research into the NMDA recognition site. It will provide a good source of reference not only for those seeking to familiarize themselves with or to enter this field, but also to workers already engaged in research on this topic. Unfortunately, I fear that the book is overpriced and this will deter some more junior researchers from buying it. For those able to afford it, the purchase of this book is to be recommended. R. S. G. JONES