Mark S. Brownfield
- Associate Professor, Department of Comparative Biosciences, School of Veterinary Medicine
- (608) 263-5863
Ph.D. Colorado State University
Role of Brain Serotonin Neurons on Neuroendocrine and Automatic Systems
Research in my laboratory seeks to understand the structural organization of the brain serotonergic system and its impact on brain function, particularly regulation of the neuroendocrine and autonomic systems. Our approaches include light and electron microscopic immunohistochemistry, neurochemistry, neuropharmacology, and whole animal physiology.
Most recently we have focused on the molecular anatomy of serotonergic neurons and their target neurons. To support this activity we have developed a panel of antibodies against the serotonergic system. These include antisera to serotonin (5-hydroxytryptamine), its precursor (5-hydroxytryptophan), and primary metabolite (5-hydroxyindole acetic acid). Using computer-assisted antigen design we have also generated antibodies to tryptophan hydroxylase (the rate limiting enzyme in the biosynthesis of serotonin), serotonin transporter (the target of a class of antidepressant drugs), and five serotonin receptors (5HT1a, 5HT2a, 5HT2c, 5HT5a, and 5HT7). Using this unique panel of reagents we are now performing chemical mapping of 5HT neurons relative to their receptor bearing neural targets and to other neurotransmitter systems to gain information about the functional activities of the serotonergic system. These studies reveal associations with circuits important in neuroendocrine, autonomic, emotional, circadian, visual, and motor systems.
- Nelson D.W., J.W. Sharp, M.S. Brownfield, H.E. Raybould, and D.M. Ney. 2007. Localization and activation of glucagon-like peptide-2 receptors on vagal afferents in the rat. Endocrinology 148:1954-62
- Dimitrov E.L., M.R. Dejoseph, M.S. Brownfield, and J.H. Urban. 2007. Involvement of neuropeptide Y Y1 receptors in the regulation of neuroendocrine corticotropin releasing hormone neuronal activity.. Endocrinology 148(8):3666–3673
- Wolak, M. L. , M. R. DeJoseph, A. D. Cator, A. S. Mokashi, M.S. Brownfield, and J. H. Urban. 2003. Comparative distribution of neuropeptide Y Y1 and Y5 receptors in the rat brain by using immunohistochemistry. J. Comp. Neurol. 464: 285-311.
- Parsons M.J., R.M. Benca, M.S. Brownfield, and M. Behan. 2001. Age-associated changes in the serotonergic system in rat superior colliculus and pretectum. Brain Res Bull 55:435-44
- Neumaier, J.F., T.J. Sexton, J. Yracheta, A.M. Diaz, and M.S. Brownfield. 2000. Localization of 5-HT7 receptors in rat brain by munocytochemistry, in situ hybridization, and agonist stimulated cFos expression. J. Chem. Neuroanat. 21: 63-73.
- Duncan, M.J., L. Jennes, J.B. Jefferson, and M.S. Brownfield. 2000. Localization of serotonin(5A) receptors in discrete regions of the circadian timing system in the Syrian hamster. Brain Res. 869: 178-185.
- Brownfield, M.S., J., Yracheta, F. Chu, D. Lorenz, and A. Diaz. 1998. Functional chemical neuroanatomy of serotonergic neurons and their targets: antibody production and immunohistochemistry (IHC) for 5-HT, its precursor (5-HTP) and metabolite (5-HIAA), biosynthetic enzyme (TPH), transporter (SERT), and three receptors (5-HT2A, 5-ht5a, 5-HT7). Ann. N.Y. Acad. Sci. 861: 232-233.