The University of Georgia College of Veterinary Medicine

eorgia Veterinary Scholars Program

GVSP Summer 2008 Scholars

Georgia Veterinary Scholar	Faculty Mentor

Annie Page University of Georgia Class of 2011	Dr. Gaylen Edwards

Expression of CB1 Receptor on Rat Nodose Ganglion Cells

Page, Annie*. Freeman, Kimberly; and Edwards, Gaylen. University of Georgia College of Veterinary Medicine, Athens, GA

Cannabinoids are a class of compounds that have the ability to activate two specific receptor subtypes, the cannabinoid CB1 and CB2 receptors, which are G-protein-coupled receptors linked to signal transduction pathways. A growing body of evidence suggests that the endocannabinoid system regulates energy
metabolism through direct effects on peripheral tissues as well as central effects that regulate appetite. Cholecystokinin (CCK) is a peptide released from the I-cells of the duodenum that activates vagal afferentneurons in response to a meal and contributes to the process of satiety. The overall purpose of this study is to
identify the CB1 receptor on cultured rat nodose ganglion neuronal cells, and to show that these cells are activated by the application of CCK. Nodose ganglion cells were isolated from male Sprague-Dawley rats and cultured in HDMEM +10% FBS solution. The CB1 receptor was identified and visualized using fluorescence
immunohistochemistry. Cells were then double-labeled for Substance P to identify C fiber-associated neurons. These data imply that cannabinoids can act on nodose ganglion neurons to alter chemosensory input from the gut. The confirmed presence of the CB1 receptor on the cells provides support for subsequent studies. The final study examines the response of cultured nodose ganglion neuronal cells to application of CCK. The results suggest that cannabinoids may act on nodose ganglion neurons to suppress neuronal
activation by gastrointestinal signals. Peripheral administration of cannabinoid agonists may thus be an important method for increasing appetite in inappetant individuals without side effects, such as euphoria, that originate in the central nervous system.

Research Support: UGA OVPR

Student Support: NIH T35 RR022685