Neurochemical characterization of the rodent primary sensory system

Abstract

Primary sensory neurons and their associated tissues are important targets for neurochemical study. Disorders of the sensory system, including chronic pain and itch, can be extremely devastating and, in many cases, difficult to treat. Part of the difficulty of treating such disorders is the limited understanding that we have for the multitude of chemical players involved in the communication of sensation within the nervous system. One particular set of intercellular signaling molecules, neuropeptides, are known to play an important role in the transmission of pain and itch signals from the peripheral system to the spinal cord. While we have a basic understanding of how many of these molecules are involved in sensory transmission, further knowledge would be benefited by more accurate and spatially relevant sampling and characterization. However, due to their low concentration and dynamic presence, the detection of these molecules in a non-targeted manner poses a unique challenge. This dissertation focuses on characterizing the peptides found in the tissues of the sensory system and released from primary sensory neurons in culture as well as improving culturing and stimulation paradigms for future research. We have worked to characterize the full content of peptides within the dorsal root ganglia, which houses the cell bodies of the primary sensory neurons, as well as other related tissues of rat and to detect changes in the peptide content of the dorsal root ganglia and dorsal horn upon generation of an itch model in mice. We have also designed a physiologically relevant sensory neuron culturing system and made strides toward spatially relevant release sampling and neuropeptide detection.