Muscle contraction has been the focus of scientific investigation for more than two centuries, and major discoveries have changed the field over the years. Early in the twentieth century, Fenn (1924, 1923) showed that the total energy liberated during a contraction (heat + work) was increased when the muscle was allowed to shorten and perform work. The result implied that chemical reactions during contractions were load-dependent. The observation underlying the "Fenn effect" was taken to a greater extent when Hill (1938) published a pivotal study showing in details the relation between heat production and the amount of muscle shortening, providing investigators with the force-velocity relation for skeletal muscles. Subsequently, two papers paved the way for the current paradigm in the field of muscle contraction. Huxley and Niedergerke (1954), and Huxley and Hanson (1954) showed that the width of the A-bands did not change during muscle stretch or activation. Contraction, previously believed to be caused by shortening of muscle filaments, was associated with sliding of the thick and thin filaments. These studies were followed by the classic paper by Huxley (1957), in which he conceptualized for the first time the cross-bridge theory; filament sliding was driven by the cyclical interactions of myosin heads (cross-bridges) with actin. The original cross-bridge theory has been revised over the years but the basic features have remained mostly intact. It now influences studies performed with molecular motors responsible for tasks as diverse as muscle contraction, cell division and vesicle transport.

by G. MILAZZO and M. BLANK This book contains the lectures of the fourth advanced course Bioelectrochemislry W Neroe-Muscle Function: Bioelectrochemistry, Mechanisms, Energetics and Contro~ which took place at the Majorana Center in Erice, Italy, October 20th to November 1, 1991. The scope of the course was international in terms of both sponsorship and partici pation. Sponsors included the Bioelectrochemical Society, NATO, International Union of Pure and Applied Biophysics (lUPAB), the World Federation of Scientists and the Italian National Research Council. One-third of the sixty participants were from Italy, but the majority came from eighteen other nations. Since the course was part of the International School of Biophysics, the biophysi cal point of view was emphasized in integrating the biology with the electrochemistry. Lecturers were asked to use a quantitative approach with accepted standards and proper units, since this is absolutely essential for developing an effective common language for communication across disciplines. Participants were also urged not to forget that biological systems could also be considered as physical systems. Ion channels are proteins and their properties as polyelectrolytes contribute to the specific biological properties. The existence of families of channels, with very similar structures but different selectivities, suggests that the specificities arise from slight variations of a general basic design. These perspectives on nerve-muscle function helped to make the school course a unique treatment of the subject.

Volumes I and 2 of this Plant Biotechnology series reviewed fundamental aspects of plant molecular biology and discussed production and analysis of the first generation of transgenic plants of potential use in agriculture and horticulture. These included plants resistant to insects, viruses and herbicides, which were produced by adding genes from other organisms. Realisation of the potential of plant breeding has led to a resurgence of interest in methods of altering the structure, composition and function of plant constituents, which represents an even greater challenge and offers scope for improving the quality of a wide range of agricultural products. This, in tum, has resulted in a re-evaluation of priorities and targets by industry. Volume 3 of this series considers the biochemical and gentic basis of the biosynthesis of plant products such as starch, lipids, carotenoids and cell walls, and evaluates the ways in which biosynthesis of these products can be modified for use in the food industries. Authors also cover the biosynthesis of rare secondary products and the function and application of proteins for plant protection and therapeutic use. The emphasis throughout is on the relationship between fundamen tal aspects of biosynthesis and structure-function relationships, and application of this knowledge to the redesigning and altering of plant products by molecular genetics."

Fish comprise more than 50% of all living vertebrates and are found in a wide range of highly diverse habitats like the deep sea, the shoreline, tide pools, tropical streams and sweetwater ponds. During evolution, the senses of fish have adapted to the physical conditions of the environment in which different species live. As a result, the senses of fish exhibit a remarkable diversity that allows different species to deal with the physical constraints imposed by their habitat. In addition, fish have evolved several new' sensory systems that are unique to the aquatic environment.
In this book, examples of adaptation and refinement are given for six sensory systems: The visual system, The auditory system, The olfactory system, The mechanosensory lateral line system, The taste system, The electrosensory system. In each case, the environmental conditions under which a particular group of fish lives are analyzed. This is followed by a description of morphology and physiology of the sensory system and by an evaluation of its perceptional capabilities. Finally, the sensory adaptations to the particular conditions that prevail in the habitat of a species are highlighted.
The various examples from different groups of fish presented in this book demonstrate the impressive capability of fish sensory systems to effectively overcome physical problems imposed by the environment.

Research on thrombin structure and function has progressed significantly over the past three decades. We are continually discovering new functions f()r this enzyme in biology. Yet, until quite recently, a full, detailed, three dimensional picture of its structure was difficult to attain. We believe that this text represents a turning point and, more appropriately, a new start ing point for thrombin studies. Our goal for this text is to present a thorough and rounded-out coverage of thrombin chemistry and biochem istry in order to provide the biochemist and physiologist with an excellent desk reference on almost any thrombin-related problem. This volume is organized into three general thrombin topic areas: Structure, Biochemistry, and Physiology. In Part 1, Structure, we open with the complete three-dimensional x-ray structures of two inhibited human thrombin complexes, one of which is the thrombin-hirudin com plex. These complexes are also addressed in the chapter on structural studies in solution, which include NMR, ESR, and fluorescence. Part 2, Biochemistry, includes chapters on synthetic thrombin inhibitors, protein inhibitors (e.g., antithrombin III, hirudin), and thrombin interactions with factor XIII. Part 3, Physiology, covers such topics as chemotactic activities, interactions with cell surfaces, and the vascular endothelium.

Mesodenn is a key tissue in early development. It is involved in the differentiation of almost every organ in the body, not merely as a structural component, but as an active participant in the establishment of diverse cell types. All mesodenn is derived from ectoderm. Its appearance signals the start of a significant new phase in the development of the embryo. At this time all three genn layers are now present and myriad sequences of cell and tissue interactions begin to occur which will eventually give rise to the entire embryo. The control of the growth and differentiation of the mesoderm is critical for the production of a normal individual. Indeed, disturbance of the patterning of the mesoderm or of its interaction with other tissues plays a critical part in the fonnation of most congenital anomalies. The main focus of this book is therefore on the establishment, divergence and specialisation of mesodermal derivatives. The central role of the mesoderm in development has long been appreciated and a wide literature exists on its activity in certain specialised situations. Recently, however, an impetus to its study has been provided by new approaches opened up through biotechnological advances. Many of these advances are reflected in the reports in this volume. Scientists from various disciplines have become drawn to mesodermal tissues, and this volume may help them find a framework within which their work will fit.

This volume represents the proceedings of the 9th International Proton Transport Conference, "Mechanisms and Consequences of Proton Transport" held in Leura, Australia, August 19 -21, 200 I. This conference has been held since 1971 every 3 to 4 years with few exceptions in association with the Congress of the International Union of Physiological Sciences. The first meeting was held in Frankfurt, Germany, at the Max-Planck'Institute. Countries hosting the conference have been Germany (twice), Sweden (twice), India, Canada, USA, Great Britain, and now Australia. Over the past 30 years participants at these Proton Transport Conferences have been principal contributors to the major discoveries in the physiology, biochemistry and pharmacology of gastric acid secretion. These include development of the H2-receptor blockers, defining the signaling pathways for the regulation of acid secretion, identifying the gastric proton pump, discovery and development of proton pump inhibitory drugs, and elucidating the physiology and biochemistry of Helicobacter pylori.

In recent years rapid progress has been made in the areas of T cell and B cell biology, cell-cell and cell-matrix/stroma interactions. The use of isolated subunits of the T cell receptor invariant chains has been instrumental in defining their role in signal transduction and tyrosine phosphorylation. A role of src family phosphotyrosine kinases in T cell activation has been demonstrated and several phosphotyrosine kinase substrates have been identified and their functions characterized. Homologous recombinant techniques have led to the development of murine strains that lack CD4 or CD8 expression. These models are likely to be instrumental in studying the role of T cell subsets in autoimmune disorders, tissue transplant rejection and tumor rejection. A role of major histocompatibility complex I in the development of T cell subsets and NK cells has been defined. Recent data suggest a role of interaction between plasma membrane molecules of activated T helper cells and B cells, B cells primed with plasma membrane of activated T helper cells and cytokines, and interaction between bone marrow stromal cells and B cell progenitors and precursors, in the B cell development, proliferation, and differentiation. The structure and functions of adhesion molecules, especially with regard to signal transduction and homing events, are better defined.

Serpins (serine protease inhibitors) are a superfamily of proteins whose physiologi- cal action is primarily targeted to inhibiting serine proteases. There are instances where serpins are not inhibitors (and can carry steroid hormones for instance), yet key structural and functional elements found in all serpins are maintained in these 'non-inhibitor' ser- pins. Many serpins have well-described biological properties which influence pathophysi- ological events, including: antithrombin (historically called antithrombin III), ai-protease inhibitor (historically called ai-antitrypsin), and plasminogen activator inhibitor-I, just to mention a few. A deficiency or defect in antithrombin leads to venous thromboembolic disease, while a deficiency or defect in ai-protease inhibitor is associated with chronic obstructive pulmonary emphysema. In contrast, it has been suggested that increased levels of plasminogen activator inhibitor-l may be a predisposition to myocardial infarction. The list goes on for each of our own "favorite" serpin. The biological roles found for serpins are key participants in almost every physiological event. In other words, serine proteases are needed for many events in biology and the role of serpins to down regulate these pro- teases is essential. Thus, just using these three examples above for serpins and their patho- physiological roles reminds us that the medical costs to control such events is significant worldwide.

This monograph contains the proceedings from the Advanced Study Institute on "Vascular Endothelium: Physiological Basis of Clinical Problems" which took place in Corfu, Greece in June 1990. The meeting consisted of twenty-eight lectures, most of them adapted as full length papers in this volume, as well as numerous short oral and poster communications which are abstracted and also included in alphabetical order (pages 239-302). There were ninety-six participants from ten NATO and four other European countries. The meeting was the second in as many years dealing with a specific subject in Endothelial Cell biology. Following the 1988 discussion on "Receptors and Transduction Mechanisms", the present ASI recognized and tried to deal with the increasing overlap in interest between basic scientists studying endothelial cell functions and clinicians facing problems of known or suspected endothelial pathological involvement. As with any similar effort, we opted to be selective, rather than fail by trying to be inclusive, in the subjects covered. We chose to discuss diseases, such as atherosclerosis, sepsis, ARDS and stroke, based on their relevance to endothelial cell function and urgent need for new insights into their pathogenesis and treatment. Similarly, we examined endothelial cell functions by considering their relevance to disease and their potential for elucidating important pathologies. Obviously, some areas were covered superficially or not at all; this should not distract from their importance, but rather reflect on the constraints of time and -not at all negligibly -the bias of the organizing committee.

This book deals with the cellular biology, biochemistry and physiology of photoreceptors and their interactions with the second-order neurons, bipolar and horizontal cells. The focus is upon the contributions made by these neurons to vision. Thus the basic neurobiology of the outer retina is related to the visual process, and visual defects that could arise from abnormalities in this part of the retina are highlighted in the first 16 chapters. Since all vertebrate retinas have the same basic structure and physiological plan, examples are given from a variety of species, with an emphasis upon mammals, extending to human vision. The last four chapters approach the problem from the other end. This part of the book covers a range of clinical conditions involving visual abnormalities that are due to cellular defects in the outer retina. Although the contents of this book do not represent the proceedings of a conference, the concept arose at an international symposium on 'Recent Advances in Retinal Research' which was held at the International Marine Centre in Oristano, Sardinia. We hope that the book will give a coherent, up to date review of the neurobiology and clinical aspects of the outer retina and encourage further integration of these areas. Retinal neurobiology has been an intense field of investigation for several decades. More recently, it has seen significant advances with the application of modern techniques of cell and molecular biology.

Proceedings of an international symposium, held in Ulm, Germany, September 21-24, 1994

From the 19-29 May 1991 the NATO ASI Course PAsthma Treatment: A P Multidisciplinary Approach was held in Erice, on the rocky North West Coast of Sicily, facing the ancient Phoenician shore of the African Continent. Sixty NATO sponsored participants arriving from many different European Countries - Nato members and non - attended the course. Qualified researchers from Europe and the United States held extensive lectures, short meetings and small informal group discussions. Erice is a magical place which draws together people from different backgrounds and cultures under her Mediterrean charm, recreating the ancient Greek openair discussion atmosphere. And so, during the 10 days gathering, the extensive willingness of the senior investigators and the laudable enthusiasm of the younger participants was stimulated. All of the most recent findings in the biology and the pharmacology of Asthma were discussed, initially behind closed doors, to be unhurriedly continued along the alley ways of the "Cittadella della Scienza" , in Erice's small restaurants, and on her deserted beaches. The texts collected here are testimony to the high quality of the investigators contributions as well as their far reaching interests. I think that a Director of such a Course would be adequatly satisfied by merely considering the enthusiasm and high level involvement of every participant. He could not have been more satisfied after having considered the proceedings summerizing the scientific content of the meeting.

From within complex structures of organisms and cells down to the molecular level, biological processes all involve movement. Muscular fibers slide on each other to activate the muscle, as polymerases do along nucleic acids for replicating and transcribing the genetic material. Cells move and organize themselves into organs by recognizing each other through macromolecular surface-specific interactions. These recognition processes involve the mu tual adaptation of structures that rely on their flexibility. All sorts of conformational changes occur in proteins involved in through-membrane signal transmission, showing another aspect of the flexibility of these macromolecules. The movement and flexibility are inscribed in the polymeric nature of essential biological macromolecules such as proteins and nucleic acids. For instance, the well-defined structures formed by the long protein chain are held together by weak noncovalent interac tions that design a complex potential well in which the protein floats, permanently fluctuating between several micro- or macroconformations in a wide range of frequencies and ampli tudes. The inherent mobility of biomolecular edifices may be crucial to the adaptation of their structures to particular functions. Progress in methods for investigating macromolecular structures and dynamics make this hypothesis not only attractive but more and more testable.

The symposium on Acoustical Signal Processing in the Central Auditory System which was held in Prague on September 4--7, 1996 was the third in a series organized in Prague, after the Neuronal Mechanisms of Hearing symposium in 1980 and Auditory Pathway - Structure and Function symposium in 1987. Approximately 100 scientists regis tered for the symposium and presented 82 separate papers and posters. The present vol ume contains 53 of these contributions, mostly presented at the symposium as invited review papers. Several essential changes occurred since the previous meeting in 1987. In auditory neuroscience, recently developed methods opened new horizons in the investigation of the structure and function of the central auditory pathway. Methods like c-fos tracing tech niques and monoclonal antibodies for neurotransmitters and their receptors, like the intro duction of electrophysiological recording from brain slices have made possible new insights into the function of individual neurons and their interconnections, particularly in the cochlear nuclei and in the superior olivary complex. Integrative approaches towards understanding the central auditory function started to dominate in the field. It is not easy at the present time to differentiate between purely morphological and neurochemical ap proaches; similarly electrophysiological approaches are accompanied inevitably by behav ioral and psychophysical studies. The understanding of human brain function advanced significantly during the last several years. mainly due to the contribution of magneto encephalography. positron emission tomography and functional nuclear magnetic reso nance imaging.

One of the most impressive advances in the field of neuroscience over the last decade has been the accumulation of data on plasticity and regeneration in the nervous system of mammals. The book represents the contribution of a qroup of neuroscientists to this rapidly expanding field, through a Conference organized by the Institute of Developmental Neuroscience and Aging (IDNA). The meeting was held in Torino, Italy during April 1990 in honor of a great pioneer in the field of Neuroembryology, Professor Guido Filogamo. His introduction of the concept of neuroplasticity has had a significant impact on the study of neurobiology. This volume is divided into six sections, each focusing on one of the subject areas covered during the meeting Molecular and Cellular Aspects of Central and Peripheral Nervous System Development; Hormones,* Growth Factors, Heurotransmi tters, Xenobiotics and Development; In Vivo and in Vitro models of Development; Development and Regulation of Glia; Regeneration; and Aging.

Birds and reptiles have long fascinated investigators studying hearing and the auditory system. The highly evolved auditory inner ear of birds and reptiles shares many characteristics with the ear of mammals. Thus, the two groups are essential in understanding the form and function of the vertebrate and mammalian auditory systems. Comparative Hearing: Birds and Reptiles covers the broad range of our knowledge of hearing and acoustic communication in both groups of vertebrates. This volume addresses the many similarities in their auditory systems, as well as the known significant differences about hearing in the two groups.

The cardiac system represents one of the most exciting challenges to human ingenuity. Critical to our survival, it consists of a tantalizing array of interacting phenomena, from ionic transport, membrane channels and receptors through cellular metabolism, energy production to fiber mechanics, microcirculation, electrical activation to the global, clinically observed, function, which is measured by pressure, volume, coronary flow, heart rate, shape changes and responds to imposed loads and pharmaceutical challenges. It is a complex interdisciplinary system requiring the joint efforts of the life sciences, the exact sciences, engineering and technology to understand and control the pathologies involved. The Henry Goldberg Workshops were set up to address these multivariable, multidisciplinary challenges. Briefly, our goals are: To encourage international cooperation and foster interdisciplinary interaction between scientists from the different areas of cardiology; to relate microscale cellular phenomena to the global, clinically manifested cardiac function; to relate conceptual modeling and quantitative analysis to experimental and clinical data; to gain an integrated view of the various interacting parameters, identify missing links, catalyze new questions, and lead to better understanding of the cardiac system. The outstanding success of past workshops has encouraged their continuation. The first Henry Goldberg Workshop, held in Haifa in 1984, introduced the concept of interaction between mechanics, electrical activation, perfusion and metabolism, emphasizing imaging in the clinical environment. The second Workshop, in 1985, discussed the same parameters with a slant towards the control aspects.

From recent developments in the rapidly growing area of neuroscience it has become increasingly clear that a simplistic description of brain function as a broad collection of simple input-output relations is quite inadequate. Introspection already tells us that our motor behavior is guided by a complex interplay between many inputs from the outside world and from our internal "milieu," internal models of ourselves and the outside world, memory content, directed attention, volition, and so forth. Also, our motor activity normally involves more than a circumscribed group of muscles, even if we intend to move only one effector organ. For example, a reaching movement or a reorientation of a sensory organ almost invariably requires a pattern of preparatory or assisting activities in other parts of the body, like the ones that maintain the body's equilibrium. The present volume is a summary of the papers presented at the symposium "Sensory Interaction in Posture and Movement Control" that was held at Smolenice Castle near Bratislava, Slovakia, as a Satellite Symposium to the ENA Meeting 1994 in Vienna. The focus of this meeting was not only restricted to the "classical" sensory interactions such as between vestibular and visual signals, or between otolith and semicircular canal inputs. Rather, the symposium tried to consider also the interplay between perception and action, between reflexive and volitional motor acts as well as between sensory driven or self-initi ated motor acts and reafferent inputs."

This volume contains the papers presented at the International Symposium on "Cirrhosis, Hyperammonemia and Hepatic Encephalopathy," held in Valencia, Spain, De- cember 2nd_4th, 1996. Liver cirrhosis is one of the main causes of death in occidental countries. There are other hepatic dysfunctions such as fulminant hepatic failure, Reye's syndrome, or congenital deficiencies of urea cycle enzymes which can also lead to hepatic encephalopathy, coma and death. However, the molecular bases ofthe pathogenesis of hepatic encephalopathy remain unclear. One ofthe consequences of hepatic failure is the reduced ability to detoxify ammonia by incorporating it into urea. This leads to increased blood ammonia levels. Hyperam- monemia is considered one of the main factors responsible for the mediation of hepatic encephalopathy and classical clinical treatments are directed towards reducing blood ammo- nia levels. Altered neurotransmission is an essential step in the pathogenesis of hepatic encephalopathy. The first part of the book is devoted to the discussion of the recent advances in the understanding of the alterations of different neurotransmitter systems in hepatic encephalopathy. The alterations of tryptophan metabolism and neurotransmission in hepatic encephalopathy and the implications for the clinical use of neuropsychoactive drugs are reviewed. The alterations in glutamate transport and neurotransmission in hepatic encephal- opathy due to acute liver failure are also reviewed. The role of NMDA receptors in the molecular mechanism of acute ammonia toxicity is discussed as well as its modulation by metabotropic glutamate receptors and muscarinic receptors.

In Volume 12, eminent international ornithologists further elucidate endocrinological correlates of mating strategies and hormones and reproductive behavior; assess the value of the ''brood reduction hypothesis'' in explaining ''the paradox of hatching asynchrony''; and explore the validity and sensitivity of growth bands in feathers as an indication of nutritional condition and the use of feather banding in studying growth. Chapters are well supported with charts, maps, schematic diagrams, and photographs. Current Ornithology is the only English-language publication currently devoted exclusively to extensive reviews and synthesis of topics pertaining to all aspects of the biology of birds. Chapters fall under such diverse rubrics as ecology, evolution, behavior, phylogeny, behavioral ecology, anatomy and physiology, and conservation biology. All authors are leading authorities on their subjects, and each chapter is refereed by experts in the topics covered. Although all chapters focus primarily on birds, some topics, such as the social cognition of birds as compared to primates (Volume 13), have significant application to disciplines outside of ornithology. Current Ornithology aims to provide an accessible, up-to-date, accurate source of data and to contribute to conceptual generalization and unification across the biological sciences.

This book represents Part 2 of a venture started by distinguished neuroscientists to visualize and advertise the experimentally advantageous preparations of the crustacean nervous system. The advantage is a combination of ease of dissection of key structures and the possibility of repeatedly accessing identified individual cells to measure the detailed response of the system to the experimentally imposed stimulus program. Of course, the neurosciences have to focus their research on the nervous system of mammals and man in order to understand the principles of function and their regulation if malfunctions occur. This is in line with efforts to investigate nervous systems throughout the animal kingdom. The specific potential of the encountered systems for exploratory research into hitherto unexplained functions of the brain may very well be a key to new insights. The simply organized nervous system of crustaceans performs tasks of vital importance imposed on the organism. Hence this system consists of a complete set of neural circuitry open for inspection and measurement by systematic investigation. The first volume, The Crustacean Nervous System, contains exhaustive reports on experimental work from all sectors of neuroscience using crayfish and lobsters. This second volume, Crustacean Experimental Systems in Neurobiology," contains excellent reviews on significant topics in neurobiology. Each section is introduced by short texts written by the section editors of the Crustacean Nervous System. More, prominent authors explain their approach to understanding the brain using a selection of experiments involving visual orientation, neuromuscular systems and identification of principles of neural processing.

The origins of what have come to be known as the "Oxford" Conferences on modelling and the control of breathing can be traced back to a discussion between Dan Cunningham and Richard Hercynski at a conference dinner at the Polish Academy of Sciences in 1971. Each felt that they had benefited from the different perspectives from which the topic of ventilatory control was approached - predominantly physiological in the case of Dr Cunningham and predominantly mathematical in the case of Dr Hercynski. Their judgement at that time was that a conference on the control of breathing which allowed investigators with these different (but related) scientific perspectives to present and discuss their work, might prove fruitful. We would judge that this has amply been borne out, based upon the success of the series of conferences which resulted from that seminal dinner conversation. The first conference, entitled "Modelling of a Biological Control System: The Regulation of Breathing" was held in Oxford, UK, in 1978. Subsequent conferences were: "Modelling and the Control of Breathing" at Lake Arrowhead, California, in 1982; "Con cepts and Formulations in the Control of Breathing" in Solignac, France, in 1985; "Respi ratory Control: A Modeling Perspective" at Grand Lakes, Colorado, in 1988; and "Control of Breathing and Its Modelling Persepctive" at the Fuji Institute in Japan in 1991. The conferences, subsequent to the one in Oxford, have all resulted in well-received published proceedings.

The Third International Symposium on Excitation-Contraction Coupling in Skeletal, Cardiac, and Smooth Muscle, organized by George Frank, C. Paul Bianchi, and Henk E. DJ. ter Keurs, was held in Banff Centre, Banff, Alberta, Canada during June 26 to June 30, 1991. The theme of these symposia has been to recognize the similarities and dissimilarities of excitation-contraction coupling in skeletal, cardiac, and smooth muscle. Cross fertilization of concepts of excitation-contraction coupling in these three types of muscle has occurred since the early studies in the late fifties and early sixties on skeletal muscle. Investigators in each field meet only at specialized symposia which exclude investigators in the other fields. The purpose of the symposia has been to bring together international investigators studying excitation-contraction coupling in skeletal, cardiac, and smooth muscle so that we may learn from each other and hence provide a more global concept of excitation-contraction. The Third International Symposia has accomplished its objective as we recognize that calcium channels of the sarcolemma and the sarcoplasmic reticulum play key essential roles in excitation-contraction coupling in all three types of muscles. In skeletal muscle the recognition that E-C coupling consists of two parallel mechanisms, one dependent upon a dihydropyridine voltage-sensitive sensors coupled to calcium release from the terminal cisternae via the ryanodine sensitive channel in the foot structure of the triad.

This is the third meeting we have organized which has explored the meaning of fetal neural developmental disruption in the etiology of schiwphrenia. The first was sponsored by the Schiwphrenia Research Branch with the scientific cooperation of Dr. David Shore. We met in Washington; the output of the meeting was published in a book entitled, Fetal Neural Development and Adult Schizophrenia. Cambridge University Press. 1991. The next meeting was an Advanced Research Workshop sponsored by NATO and was held at n Ciocco. Castelvecchio Pascoli. This meeting was reported in a NATO volume. Developmental Neuropathology of Schizophrenia and was edited by Mednick. Cannon. Barr and La Fosse. The current meeting has noted several advances in the field. There are additional psychiatric illnesses which have been found to be related to maternal viral infection in the second trimester. There have been studies reported which have definitely observed a viral infection in the mothers of fetuses who later evidenced schirophrenia. More evidence has been published which has replicated the "second-trimester effect." In the future studies will be wise to provide serological evidence of a viral infection and information on the precise viruses involved. Another important step will be to determine whether second-trimester maternal viral infection is related to a behavioral deficit in the infant. If neural development has been compromised. it might be possible to detect deficits in the infant with the proper measures. We look forward to future meetings at which these new areas might be explored.