The experiments to be conducted in this project cover the topics of the synaptic action of neuropeptides, synaptic plasticity, and colocatization of transmitters. An examination of these topics in the context of the lumbosacral autonomic system will expand knowledge of the neural control of excretory function and at the same time provide information which will have a broad impact on several areas of neuroscience. It is anticipated that studies of neuropeptide actions and neuronal plasticity in this autonomic system will also provide direction for studies of autonomic mechanisms at other levels of the neuraxis. In addition, these experiments should have considerable clinical relevance, by furthering understanding of neurogenic bladder dysfunction which occurs following traumatic injury or disease to the sacral spinal cord, and roots or the peripheral nerves.