With the help of recent technological advances in the study of cen- tral nervous system function, important strides have been made in our knowledge regarding the pathophysiology of high blood pres- sure. The understanding of neural mechanisms involved in the reg- ulation of the cardiovascular system is of critical importance to the development of rational approaches to both the treatment and pre- vention of this disease. It was in this spirit that a satellite symposium of the 13th Scientific Meeting of the International Society of Hyper- tension was held in June 1990, in Bethesda, Maryland. The chapters, in this first of two volumes on the same general theme, are based on lectures presented at the symposium and it is hoped that these sum- maries of recent research findings from prominent laboratories around the world will provide a stimulus for future research. The symposium would not have been possible without generous support from the National Institute on Alcohol Abuse and Alcoholism, Merck Frosst Canada, G. D. Searle Co., Squibb Institute of Medical Research, Smith, Kline & Beecham Co., Pfizer Co., E. I. Dupont de Nemours Co., Merck, Sharp & Dohme Co., The UpJohn Co., and Wyeth-Ayerst Co. While this volume was being prepared for publication, one of its contributors, Dr. Michael J. Brody, died suddenly. It is with deep sorrow and sympathy that we mourn the loss of our colleague. Dr.