Research goals of my laboratory are to understand the physiological mechanisms involved in synaptic plasticity among neurons in vivo and in situ. The phasic and tonic motor neurons associated with crayfish neuromuscular junctions (NMJ) lend themselves for relatively easy physiological and molecular experimentation. With electrophysiological tools, the intrinsic differences in synaptic efficacy of tonic and phasic neurons are being investigated. In addition, we are investigating the mechanisms underlying the synaptic plasticity involved during the experimentally induced transformation of phasic to tonic motor neurons. In this system of phasic, tonic and transformed phasic motor nerve terminal, we are assessing the effects of neuromodulators, known to be present in the crayfish hemolymph. In addition, we are examining the role of neuromodulators on alterations of activity in primary sensory neurons and the integration of the sensory input. Molecular based projects are aimed at determining which particular proteins are utilized during the various stages of synaptic transmission.