Test your understanding of neurophysiology
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430 Book Reviews The flight muscles of insects show stepwise shortening which is synchronized throughout the whole of the muscle. It is possible that similar synchronized stepwise shortening occurs during other muscle fibre contraction. There had been some doubt whether the linear fall of isometric tension with decreasing overlap, demonstrated the action of independent tension generators adding up in parallel in the region where actin filaments overlapped myosin cross bridges. The evidence presented at this meeting indicated that the cross bridges in the overlap region are all involved equivalently in the production of tension. There is also the possibility that the myosin head consists of several domains, one of which is always attached to the actin and in rigor configuration, whilst the other domains can adopt various configurations during the working stroke. The volume presents in detail the arguments in favour of these and many other ideas about the contractile mech- anisms of muscle. Mammalian Neuroendocrinology--G. W. Bennett and S. A. Whitehead. 279 pp. 1983. Oxford University Press, England. US$29.95. The links between endocrinology and neurophysiology are complex and important, and many chemicals that initially were thought to be concerned with the endocrinological systems such as TRH (thyrotropin releasing hormone) and somatostatin are now also involved as transmitters/ modulators in the CNS. The present book provides a clear and concise account of the neuroendocrine systems in mammals with special accent on the basic control and feed back loops. This is linked in with histological studies, techniques of experi- mental analysis, clinical applications of the available hormones, and the role that these compounds play in reproductive rhythms and behaviour. Most textbooks on mammalian physiology are rather weak on neuroendocrinology and the control of the endo- crinological system, and this book will make up for the deficit. Strongly recommended. Test Your Understanding of Neurophysiology--R. W. Murray. 291 pp 1983. Cambridge University Press. Cambridge. £25 hardback; £8.95 paperback. This book is in three parts. Part I: Basic principles of electricity, Ohms, Law, capacitances, exponentials, mem- brane potentials, recordin techniques, spike shapes, bridge circuits, voltage clamping. Part II: Problems, problem solving, graphs, formulae and constants, problems in ex- perimental technique, ions and membrane potentials, nerve and muscle cells, sense organs, synapse. Part III gives answers and comments. The book is very well written and the author has had a lot of experience in teaching neurophysiology to students. As a result he has been able to make things simple but rigorous. It has a very functional approach with the experimental data and the animal always in mind. A student working through this book will certainly get a good understanding of Neurophysiology (nerve, muscle and synapses), and get considerable enjoyment in the process. Brain Sllces---Edited by Raymond Dingledine. 442pp. 1984. Plenum Press, New York, London. US$50. Over the last five years there has been a surge of research publications on the properties of nerve cells and synapses in 100-700/~ thick slices of different parts of the mammalian brain. These thin slices under suitable conditions will show electrical activity up to 24 hours after isolation, and allow stable intracellular recording to be made from nerve cells in known anatomical positions. The majority of workers at present study slices of the hippocampus since the layered structure of the CA pyramidal cells, mossy fibres, granule cells, and known input tracts allow the study of synaptic transmission at specific sites, as well as studies on nerve membrane biophysics of the large CA1 cells. Slices have been made from the cerebellum, cerebral neocortex, neostriatum, locus coeruleus, and hypo- thalamus, and the present volume gives details of the results that can be obtained from each of these brain slice preparations. Though many of these studies have already been published in the literature, the reader will find the present account a very useful summary of what has been done with these different preparations. Besides studying the electrical activity it is also possible to measure the changes in extracellular ionic concentration using ion selective microelectrodes and one chapter de- scribes the local changes in external potassium concen- tration during activity in Purkinje cells, and during current passage through glial cells. During a burst of activity in a Purkinje cell, the external potassium concentration in- creased from 6 to 8 mM and fell back to 6 mM within one second of electrical activity stopping. This technique can be extended to allow studies of changes in external chloride concentration during the action of GABA at specific synapses. There is also a chapter on the optical monitoring of electrical activity using fluorescent stained hippocampal slices. It was possible to record the potential changes from ten different loci along the long axis of CA1 pyramidal cells. This showed the different time course of the changes in the dendrites, radiatum, pyramidale and oriens, during elec- trical stimulation and following addition of a drug such as picrotoxin. A pictorial display showed the simultaneous changes in optical (electrical) activity at these ten sites with time. It was also possible to measure changes in the light scattering signals from unstained hippocampal slices, following changes in electrical activity. Addition of TTX abolished these. The final chapter of the book presents a practical guide to the preparation and maintenance of brain slices. The book is well produced and illustrated and will help research workers know what is going on in the subject, and also to some extent how to start research work on brain slices; a subject that is at present in its infancy and is still capable of very exciting new developments. Recent Progress in the Study and Therapy of Brain Edema-- Edited by K. G. Go and A. Baethmann. 742pp. 1984. Plenum Press, New York, London. US$95. This volume contains the proceedings of the Fifth Inter- national Symposium on Brain Edema. The main section headings in the volume are: (I) basics of brain edema: (2) brain edema mediator compounds and biochemistry: (3) diagnosis and assessment of brain edema: (4) brain edema blood flow and metabolism: (5) ischaemic brain edema: (6) pharmacology and therapy of brain edema. Brain edema raises intracranial pressure and may even- tually result in lethal cerebral herniation. Regional edema may result in increase of tissue pressure and a reduction in local blood flow. Inadequate cerebral blood flow may induce brain edema. There can also be passage of protein through the cerebral capillary endothelium. The capillary endothelium is not a passive tissue, being capable of activities such as the synthesis of catecholamines (in vitro). Various chemical agents such as free fatty acids, pros- taglandins, kinins, and glutamate, may be involved in brain edema. Treatment with anti-inflammatory drugs interferes
Transcript of Test your understanding of neurophysiology
430 Book Reviews
The flight muscles of insects show stepwise shortening which is synchronized throughout the whole of the muscle. It is possible that similar synchronized stepwise shortening occurs during other muscle fibre contraction.
There had been some doubt whether the linear fall of isometric tension with decreasing overlap, demonstrated the action of independent tension generators adding up in parallel in the region where actin filaments overlapped myosin cross bridges. The evidence presented at this meeting indicated that the cross bridges in the overlap region are all involved equivalently in the production of tension.
There is also the possibility that the myosin head consists of several domains, one of which is always attached to the actin and in rigor configuration, whilst the other domains can adopt various configurations during the working stroke.
The volume presents in detail the arguments in favour of these and many other ideas about the contractile mech- anisms of muscle.
Mammalian Neuroendocrinology--G. W. Bennett and S. A. Whitehead. 279 pp. 1983. Oxford University Press, England. US$29.95.
The links between endocrinology and neurophysiology are complex and important, and many chemicals that initially were thought to be concerned with the endocrinological systems such as TRH (thyrotropin releasing hormone) and somatostatin are now also involved as transmitters/ modulators in the CNS.
The present book provides a clear and concise account of the neuroendocrine systems in mammals with special accent on the basic control and feed back loops. This is linked in with histological studies, techniques of experi- mental analysis, clinical applications of the available hormones, and the role that these compounds play in reproductive rhythms and behaviour.
Most textbooks on mammalian physiology are rather weak on neuroendocrinology and the control of the endo- crinological system, and this book will make up for the deficit. Strongly recommended.
Test Your Understanding of Neurophysiology--R. W. Murray. 291 pp 1983. Cambridge University Press. Cambridge. £25 hardback; £8.95 paperback.
This book is in three parts. Part I: Basic principles of electricity, Ohms, Law, capacitances, exponentials, mem- brane potentials, recordin techniques, spike shapes, bridge circuits, voltage clamping. Part II: Problems, problem solving, graphs, formulae and constants, problems in ex- perimental technique, ions and membrane potentials, nerve and muscle cells, sense organs, synapse. Part III gives answers and comments.
The book is very well written and the author has had a lot of experience in teaching neurophysiology to students. As a result he has been able to make things simple but rigorous. It has a very functional approach with the experimental data and the animal always in mind. A student working through this book will certainly get a good understanding of Neurophysiology (nerve, muscle and synapses), and get considerable enjoyment in the process.
Brain Sllces---Edited by Raymond Dingledine. 442pp. 1984. Plenum Press, New York, London. US$50.
Over the last five years there has been a surge of research publications on the properties of nerve cells and synapses in 100-700/~ thick slices of different parts of the mammalian brain.
These thin slices under suitable conditions will show electrical activity up to 24 hours after isolation, and allow
stable intracellular recording to be made from nerve cells in known anatomical positions.
The majority of workers at present study slices of the hippocampus since the layered structure of the CA pyramidal cells, mossy fibres, granule cells, and known input tracts allow the study of synaptic transmission at specific sites, as well as studies on nerve membrane biophysics of the large CA1 cells.
Slices have been made from the cerebellum, cerebral neocortex, neostriatum, locus coeruleus, and hypo- thalamus, and the present volume gives details of the results that can be obtained from each of these brain slice preparations. Though many of these studies have already been published in the literature, the reader will find the present account a very useful summary of what has been done with these different preparations.
Besides studying the electrical activity it is also possible to measure the changes in extracellular ionic concentration using ion selective microelectrodes and one chapter de- scribes the local changes in external potassium concen- tration during activity in Purkinje cells, and during current passage through glial cells. During a burst of activity in a Purkinje cell, the external potassium concentration in- creased from 6 to 8 mM and fell back to 6 mM within one second of electrical activity stopping. This technique can be extended to allow studies of changes in external chloride concentration during the action of GABA at specific synapses.
There is also a chapter on the optical monitoring of electrical activity using fluorescent stained hippocampal slices. It was possible to record the potential changes from ten different loci along the long axis of CA1 pyramidal cells. This showed the different time course of the changes in the dendrites, radiatum, pyramidale and oriens, during elec- trical stimulation and following addition of a drug such as picrotoxin. A pictorial display showed the simultaneous changes in optical (electrical) activity at these ten sites with time. It was also possible to measure changes in the light scattering signals from unstained hippocampal slices, following changes in electrical activity. Addition of TTX abolished these.
The final chapter of the book presents a practical guide to the preparation and maintenance of brain slices.
The book is well produced and illustrated and will help research workers know what is going on in the subject, and also to some extent how to start research work on brain slices; a subject that is at present in its infancy and is still capable of very exciting new developments.
Recent Progress in the Study and Therapy of Brain Edema-- Edited by K. G. Go and A. Baethmann. 742pp. 1984. Plenum Press, New York, London. US$95.
This volume contains the proceedings of the Fifth Inter- national Symposium on Brain Edema.
The main section headings in the volume are: (I) basics of brain edema: (2) brain edema mediator compounds and biochemistry: (3) diagnosis and assessment of brain edema: (4) brain edema blood flow and metabolism: (5) ischaemic brain edema: (6) pharmacology and therapy of brain edema.
Brain edema raises intracranial pressure and may even- tually result in lethal cerebral herniation. Regional edema may result in increase of tissue pressure and a reduction in local blood flow. Inadequate cerebral blood flow may induce brain edema. There can also be passage of protein through the cerebral capillary endothelium. The capillary endothelium is not a passive tissue, being capable of activities such as the synthesis of catecholamines (in vitro).
Various chemical agents such as free fatty acids, pros- taglandins, kinins, and glutamate, may be involved in brain edema. Treatment with anti-inflammatory drugs interferes
