D.A. KHARKEVICH The history of the study of ganglionic substances begins with the paper of LANGLEY and DICKINSON (1889), who established the ability of nicotine to block the neurones in the superior cervical ganglion. This was a considerable discovery as the authors ascertained that impulses were transmitted from pre- to postganglionic neurones in the autonomic ganglia. Simultaneously they indicated the possibility of pharmaco logical influence upon interneuronal transmission in autonomic ganglia. The idea of ganglionic receptors specifically sensitive to nicotine followed logically. Later, LANGLEY (1905, 1906) considered the problem of receptors with respect to neuro-effector synapses. It is remarkable that he was one of the first to put forward the theory of chemical mediation of excitation (" ... the nervous impulse should not pass from nerve to muscle by an electric discharge, but by the secretion of a special substance at the end of the nerve": LANGLEY, 1906, p. 183). In addition, LANGLEY JOHN N. LANGLEY (1852-1926) D.A. KHARKEVICH 2 and his collaborators managed to define the topography of autonomic ganglia more precisely by means of nicotine. It should be mentioned that it was he who introduced the terms "autonomic nervous system" and "parasympathetic nervous system".

D.A. KHARKEVICH The history of the study of ganglionic substances begins with the paper of LANGLEY and DICKINSON (1889), who established the ability of nicotine to block the neurones in the superior cervical ganglion. This was a considerable discovery as the authors ascertained that impulses were transmitted from pre- to postganglionic neurones in the autonomic ganglia. Simultaneously they indicated the possibility of pharmaco logical influence upon interneuronal transmission in autonomic ganglia. The idea of ganglionic receptors specifically sensitive to nicotine followed logically. Later, LANGLEY (1905, 1906) considered the problem of receptors with respect to neuro-effector synapses. It is remarkable that he was one of the first to put forward the theory of chemical mediation of excitation (" ... the nervous impulse should not pass from nerve to muscle by an electric discharge, but by the secretion of a special substance at the end of the nerve": LANGLEY, 1906, p. 183). In addition, LANGLEY JOHN N. LANGLEY (1852-1926) D.A. KHARKEVICH 2 and his collaborators managed to define the topography of autonomic ganglia more precisely by means of nicotine. It should be mentioned that it was he who introduced the terms "autonomic nervous system" and "parasympathetic nervous system".

In the early 1960s, Dr. Alexander G. Karczmar, Professor of Pharmacology and Experimental Therapeutics at the Stritch School of Medicine of the Medical Center at Loyola University of Chicago, was confronted with a certain technical problem concerning his studies of synaptic transmission by means of microelectrode methods. He thought that the problem might be resolved if he could interest a microelectrode expert such as Dr. Kyozo Koketsu in his studies. Dr. Koketsu was a past member of the Faculty of the Kurume University School of Medicine who as a Research Fellow at the Australian National University had helped Sir John Eccles, subse quently a Nobel Prize winner, in developing microelectrode procedures. After further considering the matter, Dr. Karczmar was pleasantly sur prised to discover that by coincidence Dr. Koketsu was his neighbor, serving at that time as a Research Professor at the Neuropsychiatry Institute of the University of Illinois, College of Medicine of Chicago. This was the beginning of a long relationship, as Dr. Koketsu joined Dr. Karczmar at Loyola as Professor of Pharmacology and Therapeutics and Director of the Neurophysiology Laboratory at the Stritch School of Medicine. It was not long before Dr. Syogoro Nishi-Dr. Koketsu's former colleague on the Faculty of Medicine at Kurume University, and at that time a Research Fellow in Neurophysiology at the Rockefeller Institute in New York joined Drs. Koketsu and Karczmar at Loyola. Although in due time Drs.

Hypertension is a major world-wide health problem. With high blood pressure there is a greater risk of stroke, heart attack, heart failure, kidney disease and renal failure. Far too few people realize what the risks are and what can be done to prevent these risks even in the countries where pro grams in hypertension research are active and the full significance of hyper tension is best understood. Some studies of the known hypertensive popu lation indicate that one-half or less are receiving adequate treatment, and, of those on therapy, only half have their high blood pressure satisfactorily controlled. These realizations emphasize the need to inform all segments of society throughout the world on the importance of detection and control of high blood pressure. The great incidence of hypertension makes it of para mount importance that all practicing physicians have available the latest information on diagnosis and treatment of hypertensive cardiovascular dis ease. This treatise on hypertension arrives at a time when there is an increasing recognition the world over of the importance of detecting and treating high blood pressure. The book has been edited by Dr. A. Amery and his asso ciates in the University of Leuven. Professor Amery is one of the leaders in the field of hypertension and serves on the Council of the International Society of Hypertension.

The peripheral nervous system is usually defined as the cranial nerves, spinal nerves, and peripheral ganglia which lie outside the brain and spinal cord. To describe the structure and function of this system in one book may have been possible last century. Today, only a judicious selection is possible. It may be fairly claimed that the title of this book is not misleading, for in keeping the text within bounds only accounts of olfaction, vision, audition, and vestibular function have been omitted, and as popularly understood these topics fall into the category of special senses. This book contains a comprehensive treatment of the structure and function of peripheral nerves (including axoplasmic flow and trophic func tions); junctional regions in the autonomic and somatic divisions of the peripheral nervous system; receptors in skin, tongue, and deeper tissues; and the integrative role of ganglia. It is thus a handbook of the peripheral nervous system as it is usually understood for teaching purposes. The convenience of having this material inside one set of covers is already proven, for my colleagues were borrowing parts of the text even while the book was in manuscript. It is my belief that lecturers will find here the information they need, while graduate students will be able to get a sound yet easily read account of results of research in their area. JOHN 1. HUBBARD vii Contents SECTION I-PERIPHERAL NERVE Chapter 1 Peripheral Nerve Structure 3 Henry deF. Webster 3 1. Introduction .