GARY M. MAWE
Professor
Anatomy and Neurobiology
Ph.D., Ohio State University, 1984
Postdoctoral training, Columbia University
Neural regulation of the digestive tract - understanding changes in enteric neural circuits that contribute to altered gut function in inflammatory bowel disease (IBD) and irritable bowel syndrome (IBS)
Neurons in the wall of the intestines control how the gut reacts to an ingested meal, and they regulate the processes of digestion, nutrient absorption, and waste elimination. In states of inflammation, such as Crohn’s disease or ulcerative colitis, various features of gut function, including motility, secretion and sensitivity are altered. As nerve cells of the bowel regulate all of these functions, it is likely that changes in these neurons cause the symptoms that lead to so much suffering in these individuals. Discoveries in gut neurobiology over the past two decades have provided us with a solid understanding of the components that make up gut reflex circuits, and how these neurons function under normal physiological conditions. We are now examining what changes occur in various parts of the reflex circuits and the mechanisms responsible for these changes.
Determining how the gallbladder contracts and delivers bile to the intestines
A hallmark of gallbladder disease is a decrease in the ability of the gallbladder to contract, and an associated decrease in the responsiveness of gallbladder smooth muscle (GBSM) to compounds such as acetylcholine and cholecystokinin that cause the gallbladder to contract and send bile to the intestines. The objectives of our current gallbladder studies are to understand how GBSM can be stimulated and how this translates to muscle contraction. One of our goals is to determine the cellular mechanisms that are responsible for electrical rhythmicity in GBSM. We are also in the process of elucidating the mechanisms by which excitatory compounds stimulate GBSM. Another goal is to determine how excitatory agonists alter the pattern of calcium signaling in GBSM. We are testing the concept that excitatory agonists shift calcium signaling from sparks — a smooth muscle relaxation mechanism through activation of K+ channels — to calcium waves, a signal that contributes to contraction. We are using state-of-the-art techniques to determine GBSM function from single molecules to the intact tissue. Together with our previous studies on gallbladder nerves, we expect to provide a comprehensive view of gallbladder function, which should illuminate new pathways to handle gallbladder disease.
Balemba OB, Bartoo AC, Nelson MT and Mawe GM. (2008) The role of mitochondria in spontaneous rhythmic activity and intracellular calcium waves in guinea pig gallbladder smooth muscle. American Journal of Physiology 294: G467-G476. 
Costedio MM, Hyman N, and Mawe GM. (2007) Serotonin and its role in colonic function and in gastrointestinal disorders. Diseases of the Colon and Rectum 50: 376-388.
Krauter EC, Strong DS, Brooks EM, Linden DR, Sharkey KA and Mawe GM. (2007) Changes in colonic motility and the electrophysiological properties of myenteric neurons persist following recovery from TNBS colitis in the guinea pig. Neurogastroenterology and Motility. 19:990-1000.
Lavoie B, Balemba OB, Nelson MT, Ward SM and Mawe GM. (2007) Morphological and physiological evidence for interstitial cell of Cajal (ICC)-like cells in the guinea pig gallbladder. Journal of Physiology 579:487-501.
Foley KF, Pantano C, Ciolino A and Mawe GM. (2007) IFN-γ and TNF-α decrease serotonin transporter function and expression in intestinal epithelial cells. American Journal of Physiology 292:G779-G784.
Krauter EC, Linden DR, Sharkey KA and Mawe GM. (2007) Synaptic plasticity in guinea pig myenteric neurons: Presynaptic mechanisms of inflammation-induced synaptic facilitation. Journal of Physiology 581: 787-800.
For more papers by Gary Mawe, click here.
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Mawe Lab - July, 2008: (L to R) Gary Mawe, Jill Hoffman, Elice Brooks, Brigitte Lavoie, Onesmo Balemba, Derek Strong, Carson Cornbrooks, Jane Roberts.
Mawe Lab - June, 2007; May, 2003
Eric Krauter's Defense Party - June, 2007
