The primary objective of this US-Hungary cooperative research project between Dr. Vera Adam-Vizi of Semmelweiss University of Medicine, Budapest and Dr. Abel Lajtha of the N.S. Kline Institute, Orangeburg, NY is to examine the mechanism of which calcium is released when nerves release neurotransmitters, causing a concentration in extracellular fluids. The researchers intend to 1) differentiate between a non-specific increase in external calcium and one which is due to calcium released from nerve terminans; and 2) identify which fraction of the neurotransmitter stored in nerve terminals is susceptible to changes in external calcium concentration. Results may reveal molecular mechanisms which are associated with transmitter secretion. Funds for the project are awarded through the U.S.-Hungary Joint Fund, Budapest in accordance with established guidelines.