FROM INVERTEBRATES TO MAMMALS: FOLLOWING INTRACELLULAR PEPTIDERGIC COMMUNICATION

Professor Sweedler’s research program emphasizes two major interlocking areas. The first is development of analytical methods that allow trace components to be assayed in complex biological microenvironments; the second is application of these methods to improve our understanding of cellular communication and neurotransmitter distribution and release. These two efforts are synergistic in that new measurement tools allow the probing of details of learning and memory, while new understanding leads to more questions, which often require advances in measurement strategies. Much of his work involves scaling a variety of methods to the nanoliter or smaller volume regime in order to identify and quantify neuroactive compounds from cellular microenvironments. His group has developed several unique capillary separation, spectroscopic, and mass spectrometric systems that allow low-concentration assays of several classes of signaling molecules from microenvironments. Using these techniques, the group studies interactions of neurotransmitters and neuropeptides using the well-defined neuronal networks in the simpler nervous systems of opisthobranch molluscs to understand the implications of neurotransmitter cotransmission in regulating behavior. During his Center appointment, Professor Sweedler will adapt several of these technologies to work with mammalian brain slices to probe the interaction of multiple neuropeptides in several partially characterized systems, including the rat suprachiasmatic nucleus.