James McRoberts, PhD

Professor, Vatche and Tamar Manoukian Division of Digestive Diseases, Department of Medicine, David Geffen School of Medicine at UCLA

Dr. McRoberts’ research focuses on the mechanisms involved in visceral pain, particularly that associated with the GI tract. He uses in vitro biological approaches to examine neurons and neurotransmission at the cellular and molecular level. He also examines behavioral responses to various visceral pain paradigms with an emphasis on stress modulation of pain perception. The specific goal of Dr. McRoberts’ project is to determine the role of peripheral N-methyl-D-aspartate-type glutamate receptors (NMDARs) expressed on extrinsic primary afferent nerves in visceral and somatic pain transmission and in the development of peripheral and central sensitization.  Using various molecular techniques and whole cell patch clamp methodology, he has identified the NMDAR subunits expressed by different subtypes of dorsal root ganglia (DRG) neurons, characterized the functional and pharmacological properties of these receptors, identified their role in modulating afferent sensitivity to mechanical distension of the colon, demonstrated that NMDARs in DRG neurons regulate voltage-dependent calcium channels through PKC activation, and shown that colonic inflammation leads to persistent up-regulation in NMDAR channels with altered pharmacological properties .  He has also developed mice with tissue specific knock out of NMDARs in DRG neurons and shown that these mice have diminished nociceptive responses during phase 2 of the formalin test, thus demonstrating that these receptors participate in the process of central sensitization. The long-term goal of this research is find better means to control pain of visceral origin in order to help patients with functional bowel diseases such as IBS.


James McRoberts
UCLA Med-Div of Digestive Dis
BOX 951786, 14-103 Warren Hall
Los Angeles, CA 90095-1786