Frog Neurobiology A Handbook

Edited by R.Llinas and WPrecht

Contributors R. R. Capranica . W T. Catton' P. Clairambaul t . G. Czeh K. O. Donner' J. E. Dowling· S. O. E. Ebbesson' R. C. Gesteland B. L. Ginsborg . 1. Grofova' O.-J. Grusser' U. Grusser-Cornehls W Hanke' B. Hille' D. E. Hillman' M. Hollyday· A. Hughes D. Ingle' C. B. Jaeger' E. Kic1iter' G. Lazar' B. Lindemann' R.Llinas L. Mendell· Hk. Muller' R. Nieuwenhuys . P. Opdam . D. Ottoson W. Precht· T. Reuter' 1. J. Russell' M. Sato' F. Scalia' P. C. Schwindt J.1. Simpson' C. Sotelo' D. C. Spray' R. Stampfli· J. H. Steinbach C. F. Stevens' G. Szekely· J. Taxi' C. Voute.

With 711 Figures

Springer-Verlag Berlin Heidelberg New York 1976

Dr. RODOLFO LUNAS, Professor of Physiology and Biophysics, Department of Physiology and Biophysics, New York University, School of Medicine, 550 First Avenue, New York, N.Y. 10016 USA

Dr. WOLFGANG PRECHT, PD. Adj. Professor of Physiology, Neurobiologische Abteilung, Max-Planck-Institut fUr Hirnforschung, 6000 Frankfurt-Niederrad, Deutschordenstra13e 46, Federal Republic of Germany

ISBN-13: 978-3-642-66318-5 DOl: 10.1007/978-3-642-66316-1

e-ISBN-13: 978-3-642-66316-1

Library of Congress Cataloging in Publication Data. Main entry under title: Frog neurobiology. Includes bibliographical references and index. I. Neurobiology. 2. Frogs~Physiology. I. Llinas, R. II. Precht, W., 1938-III. Capranica, Robert R. QP356.F74 597'.8 75-46505

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© by Springer-Verlag Berlin· Heidelberg 1976.

Softcover reprint of the hardcover 1st edition 1976

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Preface

In review, the amount of information available on the morphological and func­tional properties of the frog nervous system is very extensive indeed and in certain areas is the only available source of information in vertebrates. Further­more, much of the now classical knowledge in neurobiology was originally ob­tained and elaborated in depth in this vertebrate. To cite only a few examples, studies of nerve conduction, neuromuscular transmission, neuronal integration, sense organs, development, and locomotion have been developed with great detail in the frog and in conjunction provide the most complete holistic descrip­tion of any nervous system. Added to the above considerations, the ease with which these animals may be maintained (both as adults and during development) and the advantage of their lower cost as compared with other vertebrate forms make the frog one of the most important laboratory animals in neurobiology.

With these thoughts in mind, we decided to compile this volume. Our goal in doing so was to assemble as much as possible of the information available on frog neurobiology and to have the different topics covered by authorities in each of the fields represented. To keep the handbook restricted to one volume, we found it necessary to omit the large field of amphibian muscle neurobiology, which has already been summarized in various other publications. Instead, the physiology and morphology of the amphibian skin - often neglected in neurobiol­ogy textbooks-was incorporated in order to draw attention to this increasingly important field of research. The basic philosophy for each chapter was to provide an in-depth presentation in the true sense of a handbook, with a complete bibliography, historical background, and an up-to-date description of the areas treated. Now, with all the contributions at hand, we find our expectations more than satisfied, the actual size of the volume being, in fact, larger than we had originally anticipated. It is our hope that our colleagues will find this handbook as instructive as we ourselves found it during our editorial review.

The editors wish to express their appreciation to the contributors for their efforts in making this handbook a state-of-the-art report, and to the publishing staff at Springer-Verlag for fulfilling the contributors' wishes at the various stages of the production of this book. Finally, we are deeply indebted to Miss ELLEN ADAMS for coordination of material and preparation of the index.

RODOLFO LUNAS and WOLFGANG PRECHT Editors

Contents

Section I. Peripheral Systems

1. Electrophysiology of the Peripheral Myelinated Nerve. R. STAMPFLI and B. HILLE. With 17 Figures ................... .

1 Preparation, Morphology, and Excitation of Single Myelinated Fibers 2 Biophysics of Ionic Permeability Mechanisms at the Node of Ranvier 3 Conclusion 4 Summary ............... .

2. Neuromuscular Transmission. J.H. STEINBACH and C.F. STEVENS. With 9 Figures ........... .

Introduction . . . . . . . . . . . . 2 Structure and Functional Localizations 3 Biochemistry . 4 Physiology . . 5 Pharmacology 6 Summary

3. Morphology of the Autonomic Nervous Systems. J. TAXI. With 45 Figures

1 Anatomy 2 The Ganglia 3 The Peripheral Autonomic Innervation 4 Summary ............ .

4. Physiology of the Autonomic Nervous System. B.L. GINSBORG. With 18 Figures .

1 Introduction . . . . . . . . . . . 2 The Periphery . . . . . . . . . . 3 Autonomic Ganglionic Transmission 4 Summary ........... .

5. Structure and Function of the Epidermis. B. LINDEMANN and C. VOUTE. With 23 Figures . . . . . . . .

1 Why is Frog Skin Interesting? 2 Structure of the Epidermis . 3 Structure of the Corium . . 4 Transmural Uptake of NaCl 5 Inside the Black Box 6 Regulation and Mechanism of Water Transport 7 Transport Effects of Hormones and Transmitters

3

3 12 27 27

33

33 34 37 37 55 77

93

93 97

125 142

151

151 151 154 166

169

169 169 177 179 181 199 202

VIII Contents

Section II. Sensory Systems

Olfaction

6. Structure of the Olfactory and Accessory Olfactory Systems. F. SCALIA. With 11 Figures . . . . . . . . . 213

1 Introduction . . . . . . . . . . . . . . . . . . . . . . 213 2 The Peripheral Olfactory System . . . . . . . . . . . . . 214 3 Structure of the Olfactory Bulb and Accessory Olfactory Bulb 218 4 General Structure of the Telencephalon . . . . . . . . . . 220 5 Experimental Analysis of the Central Olfactory and Accessory Olfactory

Pathways 228 6 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . .. 232

7. Physiology of Olfactory Reception. R.C. GESTELAND. With 7 Figures ................ 234

Introduction . . . . . . . . . . . . . . . . 234 2 Olfactory and Vomeronasal Receptor Organ Anatomy . 234 3 Olfactory Behavior . . . . . . . . . . . . . . 235 4 Dynamic Morphology of Olfactory Receptor Cells 235 5 Olfactory Organ Electrophysiology . . . . . . 237 6 Action Potentials in Olfactory Receptor Neurons 244 7 Summary . . . . . . . . . . . . . . . . . 247

Vision

8. Visual Pigments and Photoreceptor Function. K.O. DONNER and T. REUTER. With 16 Figures . . . . . . . . . . . . . . . . . . . . . . . . 251

I The Visual Cells . . . . . . . . . . . . . . . . . . . . . . 251 2 The Properties and Spectral Characteristics of the Visual Pigments 255 3 Spectral Properties of the Electroretinogram and the Ganglion Cell

Discharge . . . . . . . . . . . . . . . . . . . . . . . . . 259 4 The Bleaching and Regeneration of the Visual Pigment . . . . . 261 5 Excitation and Adaptation of the Receptors in Relation to Bleaching and

Regeneration of the Visual Pigment . . . . . . . . . . . . . . .. 268 6 Summary . . . . . . . . . . . . . . . . . . . . . . . . . .. 271

9. Physiology and Morphology of the Retina. J.E. DOWLING. With 10 Figures 278

1 Introduction . . . . 278 2 Light Microscopy. . 278 3 Electron Microscopy 280 4 Synaptic Pathways 288 5 Intraretinal Recording 290 6 A Model of the Synaptic Organization of the Mudpuppy Retina 293 7 Summary . . . . . . . . . . . . . . . . . . . . . . . 294

10. Neurophysiology of the Anuran Visual System. O.-J. GRUSSER and U. GRUSSER-CORNEHLS. With 83 Figures 297

I Introduction . . . . . . . . . . . . 297 2 Eyes, Visual Field and Eye Movements 298 3 Classes of Retinal Ganglion Cells . . . 305 4 Quantitative Investigations of Retinal Neuron Responses 316 5 Comparative Studies of Anuran Retinal Ganglion Cell Responses 333 6 The Neurophysiology of the Tectum Opticum 335 7 Visually Activated Neurons in the Diencephalon . . . . 350 8 Visual Neuronal Responses of the Telencephalon . . . . 354 9 Visual Responses in the Vestibular Nuclei and Cerebellum 355

Contents IX

10 Correlations between Neuronal Responses and Behavioral Patterns 357 11 Models and Concepts . . . . . . . . . . . . . . . . . . . . 368

11. The Optic Pathway of the Frog: Nuclear Organization and Connections. F. SCALIA. With 16 Figures 386

1 Introduction . . . . . . . . . . . . . . . . . . . . 386 2 The Optic Pathway . . . . . . . . . . . . . . . . . 386 3 Terminal Neuropil and Cell-Masses in the Optic Pathway 391 4 Further Connections within the Visual System 402 5 Development of the Optic Pathway . . . . . . . . . . 404 6 Summary . . . . . . . . . . . . . . . . . . . . . 404

12. Cellular and Synaptic Architecture of the Optic Tectum. G. SZEKELY and G. LAZAR. With 11 Figures . . . 407

1 Introduction . . . . . . . . . 407 2 Histology of the Optic Tectum . 407 3 Synaptology of the Optic Tectum 413 4 The Tectal Circuitry 429 5 Summary . . . . . . . . . . 432

13. Behavioral Correlates of Central Visual Function in Anurans. D. INGLE. With 3 Figures ........... 435

1 Introduction . . . . . . . . . . . 435 2 Retinal Encoding of the Visual Image 436 3 Analysis of the Prey-Detection System 436 4 Plasticity in Prey-Catching Behavior. 438 5 Releasers of Avoidance . . . . . . 441 6 Detection of Stationary Objects. . . 443 7 Orientation toward Maximal Light Intensity 444 8 The Accessory Optic System and Optokinetic Nystagmus 446 9 Binocular Vision . . . . . 446

10 Telencephalic Visual System 449 11 Summary . . . . . . 449

Vestibular and Lateral Systems

14. Morphology of Peripheral and Central Vestibular Systems. D.E. HILLMAN. With 32 Figures . . 452

1 Introduction . . . . . 452 2 Bony Labyrinth 452 3 Membranous Labyrinth 453 4 Perilymphatic Space. . 455 5 Vestibular Nerve Branching 455 6 Receptor Areas . . . . . 457 7 Receptor Epithelium 462 8 Primary Afferent System. 476 9 Efferent Vestibular System 478

10 Efferent Projections of the Vestibular Nuclei 478 11 Afferents to Vestibular Nuclei 478 12 Summary . . . . . . . . . . . . . . . 479

15. Physiology of the Peripheral and Central Vestibular Systems. W. PRECHT. With 18 Figures . . . . 481

1 Introduction . . . . . . . . . . . . . 481 2 Vestibular Receptors . . . . . . . . . 481 3 Responses of Primary Vestibular Neurons 482 4 Efferent Vestibular System . . . . . . . 489

x

5 Responses of Neurons in the Vestibular Nuclei 6 Vestibulo-Ocular Relationship 7 Vestibulo-Spinal Relationship 8 Summary ........ .

Contents

492 502 503 509

16. Amphibian Lateral Line Receptors. 1.1. RUSSELL. With 28 Figures

1 Introduction . . . . . . . . . . . . . . . . . . .

513

513 515 517 517 520 523 525

2 Gross Morphology and Distribution of the Lateral Line 3 Function of the Lateral Line . . . . . 4 The Ultra Structure of the Lateral Line . . . . . . 5 Development of Lateral Line Organs . . . . . . . 6 Regression and Regeneration of Lateral Line Organs 7 The Physiology of Lateral Line Organs .. . . . . 8 Functional Significance of the Responses of Afferent Fibers to Water

Displacements . . . . . . . . . . . . . . . . . . . . . . . 9 Organization of Lateral Line Input to the Central Nervous System

10 The Afferent Control of the Lateral Line System 11 Summary ........................ .

Auditory System

17. Morphology and Physiology of the Auditory System. R.R. CAPRANICA.

531 534 535 546

With 12 Figures . . . . . . 551

1 Introduction . . . . . . 551 2 External and Middle Ear 551 3 Inner Ear . . . . . . . 556 4 Auditory Nervous System 561 5 Summary . . . . . . . 572

Gustatory System

18. Physiology of the Gustatory System. M. SATO. With 7 Figures

1 Structure and Innervation of Gustatory Organs . 2 Lingual Nerve Response to Chemical Stimuli . . 3 Events at the Taste Cell and Cell-Axon Junction 4 Efferent Control of Gustatory Organs 5 Summary ................ .

19. Morphology of Gustatory Organs. C.B. JAEGER and D.E. HILLMAN. With 10 Figures . . . . . . . . . . .

1 Introduction . . . . . . . . . . . 2 General Aspects of Gustatory Organs 3 Papillary Gustatory Organs 4 Non-Papillary Gustatory Organs 5 Concluding Remarks 6 Summary ........ .

Cutaneous Receptors

20. Pain and Temperature Receptors of Anurans. D.C. SPRAY. With 23 Figures . . . . . . . . . . . . . . . . . . .

576

576 578 582 584 585

588

588 5'88 591 602 602 604

607

1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . 607 2 Anatomy of Frog Cutaneous Nerve Endings and Their Afferent Fibers 607 3 Pain Receptors in Frog Skin 611 4 Anuran Thermoreceptors 615 5 Summary . . . . . . . . 626

Contents

2l. Cutaneous Mechanoreceptors. W.T. CATTON. With 20 Figures

1 Cutaneous Innervation in Frog and Toad . . . . . 2 Categories of Frog and Toad Skin Mechanoreceptors 3 Receptor Fields 4 Receptor Thresholds ... . . . . . . . . . . 5 Response Latencies . . . . . . . . . . . . . . 6 Excitability Changes under Subliminal Stimulation 7 Responses to Ramp-and-Plateau Stimulation 8 Receptor Fatigue . . . . . . . . . . . . . . . 9 Receptor Adaptation . . . . . . . . . . . . .

10 Effects of Sympathetic Stimulation and of Catecholamines 11 Summary .................... .

Muscle Spindles

22. Morphology and Physiology of Muscle Spindles. D. OTTOSON. With 37 Figures . . . . . . .

1 The Structure of the Spindle 2 Functions of the Spindle 3 Concluding Remarks

Section III. Nervous System

Spinal Cord

XI

629

629 629 630 631 631 632 634 636 637 640 641

643

643 652 673

23. Morphology of the Spinal Cord. S.O.E. EBBESSON. With 33 Figures 679

1 General Introduction . 679 2 The Basic Organization . 680 3 Spinal Afferents . . . . 689 4 Ascending Spinal Systems 692 5 Transmitters in the Ranid Spinal Cord 701 6 Neurophysiological Correlates 702 7 Concluding Remarks and Summary . . 703

24. Ultrastructural Features of the Spinal Cord. C. SOTELO and I. GROFOVA. With 31 Figures . . . . . 707

1 Introduction . . . . . . . 707 2 Materials and Methods 707 3 Ultrastructural Observations 707 4 Summary . . . . . . . . 726

25. Functional Synaptology of the Spinal Cord. 1.1. SIMPSON. With 11 Figures . . . . . . . . . . . 728

Introduction . . . . . . . . . . . . . 728 2 The Two Motor Systems of Anurans 728 3 Motoneurons and Primary Afferent Inputs 729 4 Dorsal Root Potentials and Primary Afferent Inputs 735 5 The Descending Lateral Column Pathway 736 6 Motoneuron Activation as an Input. . . . . . . . 741 7 Summary . . . . . . . . . . . . . . . . . . . 746

26. Electrical Properties of Spinal Motoneurons. P.e. SCHWINDT. With 11 Figures . . . . . 750

Introduction . . . . . 750 2 Subthreshold Behavior 750

XII Contents

3 Antidromic Spike Components 753 4 Afterpotential Components 754 5 Rhythmic Firing Behavior . . 757 6 Accommodation Properties 758 7 Electrotonic Coupling between Motoneurons 759 8 Summary . . . . . . . . . . . . . . . 762

27. Organization of Locomotion. G. SZEKELY and G. CZEH. With 13 Figures 765

1 Introduction . . . . . . . . . . . . . . . 765 2 Locomotory Patterns in Amphibians .. . . 765 3 The Organization of the Spinal Motor Column 767 4 Spinal Control of Limb Movement 776 5 Conclusions 788 6 Summary . . . . . . . . . . . 789

28. Spinal Reflexes with Altered Periphery. L.M. MENDELL and M. HOLLYDAY. With 6 Figures .... 793

1 Introduction . . . . . . . . . . . . . . . . . . . . 793 2 Supernumerary Limbs . . . . . . . . . . . . . . . . 793 3 Wipe Reflexes in Rana pipiens with Trunk Skin Rotations 801 4 Excision of Lumbar Ganglia 805 5 General Discussion 806 6 Summary . . . . . . . . 807

Brain Stem

29. Structure of the Brain Stem. R. NIEUWENHUYS and P. OPDAM. With 24 Figures . . . 811

1 Introduction . . . 811 2 Gross Morphology 812 3 Cranial Nerves . . 813 4 The Overall Histological Pattern 815 5 Nuclei and Fiber Tracts . . 824 6 Conclusions and Comments 847

30. Metamorphic Changes in the Brain and Spinal Cord. A. HUGHES t. 856

1 Introduction . . . . . . . . . . . . . . . . . . . . . . 856 2 Endocrine Control through the Hypothalamus, Pituitary and Thyroid 856 3 Behavioral Events at Metamorphosis 858 4 Changes in Size and Shape of the Brain 858 5 The Mauthner Neurons . . . . 858 6 The Mesencephalic Nucleus of V . . . 859 7 The Spinal Cord . . . . . . . . . . 859 8 The Tail Cord and Nerves . . . . . . 860 9 The Cerebellum and the Lateral Line System 860

10 Concluding Remarks 861 11 Summary . . . . . . . . . . . . . . . 862

Cerebellum

31. Morphology of the Cerebellar Cortex. G. SOTELO. With 44 Figures

1 Introduction . . . . . . . . . . 2 Morphology of Neuronal Elements . . . . . . . . . . . . 3 Neuronal Circuits. . . . . . . . . . . . . . . . . . . . 4 Some Comparative Aspects of the Cerebellar Circuits of the Frog 5 Summary ....................... .

864

864 866 873 889 890

Contents XIII

32. Cerebellar Physiology. R. LLINAS. With 24 Figures 892

Introduction . . . . 892 2 Ablation Experiments . . . . . . . . . . . 892 3 Electrical Stimulation . . . . . . . . . . . 893 4 General Electrophysiology of the Neuronal System in the Cerebellar Cortex 893 5 In vitro Preparations . . . . . . . . . . . . 912 6 Computer Simulation of Frog Cerebellar Cortex 913 7 Summary . . . . . . . . . . . . . . . . . 921

Development

33. Development of the Prosencephalon. P. CLAIRAMBAULT. With 18 Figures

Normal Development of the Prosencephalon . . . . . 2 Morphogenetic Influences . . . . . . . . . . . . . 3 The Concept of Morphogenetic Field in the Forebrain. 4 Conclusions 5 Summary

Nonolfactory Cortex

34. Organization of the "Nonolfactory" Telencephalon. E. KICLITER and

924

924 937 940 941 944

S.O.E. EBBESSON. With 29 Figures . . . . . . . 946

1 General Introduction . . . . . . . . . . . . . . . . . . . . 946 2 Nuclear Groups in the Telencephalon of Rana . . . . . . . . . 947 3 Afferent, Efferent and Intrinsic Connections of the Ranid Telencephalon 957 4 Histochemistry of the Ranid Telencephalon . . . . . . . 964 5 Function of the "Nonolfactory" Telencephalon of Anurans 966 6 Concluding Remarks 968 7 Summary . . . . . . . . . . . . . . . . . . . . . . 969

Section IV. Neuroendocrinology

35. Neuroendocrinology. W. HANKE. With 11 Figures

1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 Structures of the Neuroendocrinological Active Areas of the Brain 3 Functional Aspects of Hormone Production in the Hypothalamus and the

Hypophysis 4 Summary

Section V. General Techniques

36. The Frog as an Experimental Animal. HK. MULLER

1 Introduction 2 Habitat ..... 3 Maintenance . . . 4 Common Diseases 5 Physiology . . . . 6 Influence of Temperature 7 Seasonal Changes . . . . 8 Experimental Procedures 9 Summary ...... .

975

975 977

995 1011

1023

1023 1023 1024 1026 1026 1029 1030 1030 1034

Subject Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1041

List of Contributors

R.R. CAPRANICA, 109 Langmuir Laboratory, Section of Neurobiology and Behavior, Cornell University, Ithaca, N.Y. 14853/USA

W.T. CATTON, Department of Physiology, Medical School, The University, Newcastle upon Tyne, NEI 7RU/Great Britain

P. CLAIRAMBAULT, Equipe de Neuroembryologie, Universite Paris VII, 2 Place Jussieu Paris, 75221 Paris Cedex 5/France

G. CZEH, Department of Anatomy, University Medical School, Szigeti u. 12, 7643 Pecs/ Hungary

K.O. DONNER, Department of Zoology, P. Rautatiekatu 13, 00100 Helsinki lO/Finland

J.E. DOWLING, The Biological Laboratories, Harvard University, 16 Divinity Avenue, Cambridge MA 02138/USA

S.O.E. EBBESSON, Departments of Neurological Surgery and Anatomy, University of Virginia, Charlottesville, VA 2290I/USA

R.C. GESTELAND, Department of Biological Sciences Northwestern University, Evanston, IL 60201/USA

B.L. GINSBORG, Department of Pharmacology University Medical School, 1 George Square, Edinburgh EH8 9JZ/Great Britain

I. GROFOVA, Anatomical Institute, University of Oslo, Karl Johans gt 47, Oslo l/Norway

O.-J. GROSSER, Physiologisches Institut, Freie UniversiHit, Arnimallee 22, 1 Berlin 33/ Federal Republic of Germany

U. GRUSSER-CORNEHLS, Physiologisches Institut, Freie UniversiUit, Arnimallee 22, 1 Ber­lin 33/Federal Republic of Germany

W. HANKE, Zoologisches Institut, Lehrstuhl II der UniversiHit, Kaiserstr. 12, 75 Karls­ruhe/Federal Republic of Germany

B. HILLE, Department of Physiology and Biophysics, Medical School SJ-40, University of Washington, Seattle, WA 98195/USA

D.E. HILLMAN, Department of Physiology and Biophysics, New York University School of Medicine, 500 First Avenue, New York, N.Y. 10016/USA

M. HOLLYDAY, Department of Biology, Washington University, St. Louis, MO 63130/ USA

A. HUGHES t formerly of: Department of Anatomy, Case Western Reserve University, 2119 Abington Road, Cleveland, OH 44106/USA

List of Contributors xv

D. INGLE, Neuropsychology Laboratory, McLean Hospital Belmont, MA 02178/USA

C.B. JAEGER, Department of Biological Structure, University of Washington, Seattle, WA 98105/USA

E. KICLITER, School of Basic Medical Sciences, Medical Sciences Building, University of Illinois, Urbana, IL 61801/USA

G. LAZAR, Department of Anatomy, Medical University, 4012 Debrecen/Hungary

B. LINDEMANN, II. Physiologisches Institut der UniversiHit des Saarlandes, 6650 Hom­burg, Saar/Federal Republic of Germany

R. LLINAS, Department of Physiology and Biophysics, New York University School of Medicine, 550 First Avenue, New York, N.Y. 10016/USA

L. MENDELL, Department of Physiology and Pharmacology, Medical Center, Duke University, Durham, NC 277l0/USA

HK. MULLER, Zentrum der Physiologie der J.W. Goethe UniversiUit, Theodor Stern­Kai 7, 6 Frankfurt, Main/Federal Republic of Germany

R. NIEUWENHUYS, Department of Anatomy, University of Nijmegen, Geert Grooteplein Noord 21, Nijmegen/The Netherlands

P. OPDAM, Katholieke Universiteit, Anatomisch-Embryologisch Laboratorium, Geert Grooteplein Noord 21, Nijmegen/The Netherlands

D. OTTOSON, Department of Physiology II, Karolinska Institutet, 10401 Stockholm/ Sweden

W. PRECHT, Neurobiologische Abteilung, Max-Planck-Institut fUr Hirnforschung, Deutschordenstr. 46, 6 Frankfurt, Main-Niederrad/Federal Republic of Germany

T. REUTER, Department of Zoology, Division of Physiology, University of Helsinki, Arkadiank. 7, 00100 Helsinki lO/Finland

I.J. RUSSELL, Ethology and Neurophysiology Group, School of Biology, University of Sussex, Brighton, Sussex BNl 9QG/Great Britain

M. SATO, Department of Physiology, Kumamoto University, Medical School, 2-1, 2-chome, Honjo, Kumamoto 860/Japan

F. SCALIA, Department of Anatomy, Downstate Medical Center, 450 Clarkson Avenue, Brooklyn, N.Y. Il203/USA

P.c. SCHWINDT, Seattle VA Hospital, General Medical Research, 4435 Beacon Avenue South, Seattle, WA 98108/USA

J.I. SIMPSON, Department of Physiology and Biophysics, New York University School of Medicine, 500 First Avenue, New York, N.Y. 10016/USA

C. SOTELO, INSERM U-106, Laboratoire de Neuromorphologie, Hopital de Port Royal, 123, bd. de Port Royal, 75014 Paris/France

D.C. SPRAY, Department of Neuroscience, Albert Einstein College of Medicine, 1410 Pel­ham Parkway South, Bronx, N.Y. 10461/USA

R. STAMPFLI, I. Physiologisches Institut der UniversiHit des Saarlandes, 6650 Homburg, Saar/Federal Republic of Germany

XVI List of Contributors

l.H. STEINBACH, Department of Physiology, Yale University, School of Medicine, New Haven, CT 0651O/USA

C.F. STEVENS, Department of Physiology, Yale University, School of Medicine, New Haven, CT 0651O/USA

G. SZEKELY, Department of Anatomy, Medical University, 4012 Debrecen/Hungary

l. TAXI, Laboratoire de Neurocytologie, Universite P. et M. Curie, 12 Rue Cuvier, 75005 Paris/France

C. VOUTE, Laboratory of Experimental Nephrology, Kantonsspital, 4 Basel/Switzerland