Department of Biology
Loyola University Maryland
4501 North Charles Street
Baltimore, MD 21210-2699
Office: DS 278
Office tel: 410-617- 5239
Areas of Interest: Gastrointestinal Physiology and Nutrition
The gastrointestinal (GI) system is responsible for the digestion of food, absorption of nutrients, and removal of wastes from the body. One of the main ways the GI system accomplishes these tasks is through patterns of muscle contraction and relaxation called GI motility. Nutrients within food can cause or change the motility patterns of the GI system. One of the main goals of the Kendig lab is to understand the mechanisms by which nutrients are able to initiate or modify GI motility. There are multiple motility patterns within the GI tract: including propulsive motility (pushes chyme towards the rectum) and mixing motility patterns (helps with digestion and absorption). Through the use of video recording, computer analysis, and spatiotemporal map generation we can measure the effects of specific nutrients on these natural motility patterns in different regions of the GI tract (specifically the stomach, small intestine, and colon).
Along with measuring the motility patterns of the GI system, the Kendig lab also studies the changes in the ability of GI smooth muscle (which lines the walls of the intestines and stomach) to contract and relax. We also study the intracellular signaling pathways involved in these processes. This allows us to examine the effects of nutrients at both the tissue (muscle contractility) and organ (motility patterns) levels. We hypothesize that nutrients in the lumen of the gut activate receptors in the mucosal layer of the gut wall, which then communicate with the smooth muscle through the enteric nervous system within the intestinal wall. One goal is to determine the receptors activated by specific nutrients (e.g. amino acids or short chain fatty acids) and the chemical mediators used to signal the enteric nervous system downstream of receptor activation. The techniques used to measure muscle contractility and motility patterns can also be applied to other smooth muscle lined organs such as the urinary bladder or blood vessels.
Kendig DM, Hurst N, Bradley ZL, Mahavadi S, Kuemmerle JF, Lyall V, DeSimone J, Murthy KS and Grider JR. Activation of the umami taste receptor (T1R1/T1R3) initiates the peristaltic reflex and pellet propulsion in the distal colon. Am J Physiol Gastrointest Liver Physiol 307(11): G1100-7, 2014. PMID: 25324508
Hurst NR, Kendig DM, Murthy KS, and Grider JR. The short chain fatty acids, butyrate and propionate, have differential effects on the motility of the guinea pig colon. Neurogastroenterol Motil 26(11): 1586-96, 2014. PMID: 25223619