This symposium entitled Calcium, Neuronal Function and Transmitter Re lease, was in the framework of the regional meeting of the International Union of Physiological Sciences, that took place in Jerusalem between August 26-31, 1984. The symposium dealt with the role of calcium ions in regulation of a large number of important processes in modern neurobiology, from molecular and cellular points of view. In this context, we consider heart and most cells as ‘honorary neurons’. The meeting was comprised of lectures and quite intense discussions. We hope that the transcription of the discussions which follow the articles will give the reader a feeling of the intense, but pleasant atmosphere that per vaded during this symposium. It is our pleasure to thank Mrs. Miriam Silber, the assistant editor of this book, for her hard work in transcribing the discussions, retyping large portions of the book, and getting the approval of the authors. We express our thanks to Dr. Halina Meiri and Dr. Simona Ginsburg for their editorial assis tance. The unfailing help of Ms. Rachel Klein and Ms. Shoshana Wineberg is greatly appreciated. xxvii SECTION 1 CALCIUM CHANNELS, TRANSPORTERS & CALCIUM REGULATED CHANNELS EFFECTS OF TEMPERATURE ON SINGLE CHANNEL AND WHOLE CELL Ca CURRENTS A. M. BROWN, D. L. KUNZE, H.D. LUX AND D. L. WILSON INTRODUCTION Calcium tall currents have a large,fast component which Is not detectable when the currents are turned on or acti vated from the completely rested state (Brown et aI, 1983).