Martin Wessendorf, PhD
Associate Professor, Department of Neuroscience
Brainstem control of spinal function: methods of fluorescence microscopy
Almost everything we do and every sensation we perceive appears to be under the control of the brain. However, the mechanism by which this control is exerted is unclear. Our laboratory is interested in how the brainstem -- in particular, the serotonergic neurons of the lower brainstem -- controls the function of neurons in the spinal cord. Some, but not all, serotonergic neurons of the lower brainstem also contain other neurotransmitters -- chiefly, neuropeptides. We have examined the projections of these different types of serotonergic cells and found that there were distinct patterns of innervation: the cells containing neuropeptides predominantly innervated motor regions and the cells not containing neuropeptides innervated sensory regions. These differences suggest that these different types of serotonergic neurons have different functions. We are also localizing different types of serotonergic receptor to determine if different types of spinal neurons employ different receptors, i.e. if there is a functional organization at the level of receptors.
The techniques that we employ include sophisticated types of optical microscopy, specifically, confocal microscopy, which allows tissue to be stained with several different fluorescent labels and "optically sectioned." In addition to our studies of receptor localization we combine molecular biological methods such as in situ hybridization with fluorescent neuronal labeling. Our research has required us to engineer several novel microscopic methods and doing so has been part of the job of this work.
Gintzler, AR, Liu, NJ, Storman, EM & Wessendorf, MW 2019, 'Exploiting endogenous opioids: Lessons learned from endomorphin 2 in the female rat' Peptides, vol. 112, pp. 133-138. https://doi.org/10.1016/j.peptides.2018.12.002
Storman, EM, Liu, NJ, Wessendorf, MW & Gintzler, AR 2018, 'Physical linkage of estrogen receptor ? and aromatase in rat: Oligocrine and endocrine actions of CNS-produced estrogens' Endocrinology, vol. 159, no. 7, pp. 2683-2697. https://doi.org/10.1210/en.2018-00319
Liu, NJ, Murugaiyan, V, Storman, EM, Schnell, SA, Kumar, A, Wessendorf, MW & Gintzler, AR 2017, 'Plasticity of signaling by spinal estrogen receptor ?,?-Opioid receptor, and metabotropic glutamate receptors over the rat reproductive cycle regulates spinal endomorphin 2 antinociception: Relevance of endogenous-biased agonism' Journal of Neuroscience, vol. 37, no. 46, pp. 11181-11191. https://doi.org/10.1523/JNEUROSCI.1927-17.2017
Liu, NJ, Murugaiyan, V, Storman, EM, Schnell, SA, Wessendorf, MW & Gintzler, AR 2017, 'Estrogens synthesized and acting within a spinal oligomer suppress spinal endomorphin 2 antinociception: Ebb and flow over the rat reproductive cycle' Pain, vol. 158, no. 10, pp. 1903-1914. https://doi.org/10.1097/j.pain.0000000000000991
Leong, ML, Speltz, R & Wessendorf, MW 2016, 'Effects of chronic constriction injury and spared nerve injury, two models of neuropathic pain, on the numbers of neurons and glia in the rostral ventromedial medulla' Neuroscience Letters, vol. 617, pp. 82-87. https://doi.org/10.1016/j.neulet.2016.02.006
Liu, NJ, Schnell, S, Wessendorf, MW & Gintzler, AR 2013, 'Sex, pain, and opioids: Interdependent influences of sex and pain modality on dynorphin-mediated antinociception in rats' Journal of Pharmacology and Experimental Therapeutics, vol. 344, no. 2, pp. 522-530. https://doi.org/10.1124/jpet.112.199851
Lan Leong, M, Gu, M, Speltz-Paiz, R, Stahura, EI, Mottey, N, Steer, CJ & Wessendorf, M 2011, 'Neuronal loss in the rostral ventromedial medulla in a rat model of neuropathic pain' Journal of Neuroscience, vol. 31, no. 47, pp. 17028-17039. https://doi.org/10.1523/JNEUROSCI.1268-11.2011
Arora, D, Hearing, M, Haluk, DM, Mirkovic, K, Fajardo-Serrano, A, Wessendorf, MW, Watanabe, M, Luján, R & Wickman, K2011, 'Acute cocaine exposure weakens GABAB receptor-dependent G-protein-gated inwardly rectifying K+ signaling in dopamine neurons of the ventral tegmental area' Journal of Neuroscience, vol. 31, no. 34, pp. 12251-12257. https://doi.org/10.1523/JNEUROSCI.0494-11.2011
Liu, NJ, Chakrabarti, S, Schnell, S, Wessendorf, MW & Gintzler, AR 2011, 'Spinal synthesis of estrogen and concomitant signaling by membrane estrogen receptors regulate spinal ?- and ?-opioid receptor heterodimerization and female-specific spinal morphine antinociception' Journal of Neuroscience, vol. 31, no. 33, pp. 11836-11845. https://doi.org/10.1523/JNEUROSCI.1901-11.2011
Liu, NJ, Schnell, SA, Schulz, S, Wessendorf, MW & Gintzler, AR 2011, 'Regulation of spinal dynorphin 1-17 release by endogenous pituitary adenylyl cyclase-activating polypeptide in the male rat: Relevance of excitation via disinhibition' Journal of Pharmacology and Experimental Therapeutics, vol. 336, no. 2, pp. 328-335. https://doi.org/10.1124/jpet.110.173039