Helen E. Raybould, PhD

Professor and Chair, Department of Anatomy, Physiology and Cell Biology, School of Veterinary MedicineUniversity of California, Davis

Dr. Raybould’s research is focused on understanding the neural and humoral control mechanisms that regulate the functions of the proximal gastrointestinal tract.  Specifically, she is interested in the role of the afferent innervation of the stomach and intestine and how luminal stimuli, such as different types of nutrients, signal to activate neural and humoral pathways to regulate gastrointestinal motility and secretion as well as food intake. Her studies have shown that the vagus nerve is a key component of the afferent pathway in the brain-gut axis. She has demonstrated that afferent discharge is stimulated by the macronutrient content of the gut lumen resulting in reflex changes in gastrointestinal function and inhibition of food intake. Her studies have significantly contributed to a better understanding of the mechanisms by which lipid (long chain triglycerides) and protein activate vagal afferents (sensory transduction). These findings are of fundamental physiological importance and they have clinical implications since afferent pathways are altered in a number of GI disorders, including functional bowel disease, IBD, and postoperative ileus and in eating disorders such as obesity.  Her studies have also focused on the role of nutrient transporters in epithelial and endocrine cells in sensory transduction in the intestine and the expression of neuropeptides involved in satiety and food intake, including cholecystokinin and serotonin.