Irritable Bowel Syndrome

Overview 

Symptoms of irritable bowel syndrome (IBS) including abdominal pain are due to abnormalities in visceral sensation, characterized by increased awareness of visceral stimuli. The worsening of IBS symptoms by stress and anxiety suggest a link between cognitive and peripheral autonomic activity.

In the laboratory of Dr. Beverley Greenwood-Van Meerveld she has discovered a link between anxiety and visceral sensitivity by showing that rats predisposed to heightened levels of anxiety display a hypersensitive colon. Moreover stereotaxic administration of glucocorticoids to the amygdala increases anxiety coupled with a hypersensitive colon. Her current research builds upon an important observation that emotional states influence sensory processing and in IBS life stress and negative emotions worsen primary symptomatology. Taken together the studies in will enhance our understanding of brain-gut pathways involved in the regulation of gastrointestinal function.

For more information, please visit the Oklahoma Center for Neuroscience

Projects

  • Investigation of the mechanisms by which corticosterone acts at the level of the central nervous system (CNS) to regulate visceral sensitivity and establish whether stereotaxic placement of glucocorticoids on the amygdala modulates activity in specific CNS structures interposed between the amygdala and the spinal cord.
  • Investigating the mechanisms of visceral organ cross-talk
  • An in vivo and in vitro investigation of the mechanisms responsible for post-inflammatory visceral hypersensitivity
  • Investigating new treatments for gastrointestinal disorders

In summary: Dr. Greenwood-Van Meerveld's major research interest focuses on communication between the brain and the gut. She is currently principal investigator (PI) on two major VA grants and multiple industry-sponsored projects. She is also co-PI of an NIH P20 grant to investigate visceral organ cross-talk.

Selected Publications (from a total of 124)

  •  Myers, B and Greenwood-Van Meerveld, B. (2012) Differential involvement of amygdala corticoid receptors in visceral hyperalgesia following acute and repeated stress. Am. J. Physiol 302(2):G260-6
  • Tran, L and Greenwood-Van Meerveld, B. (2012) Amygdala Lateralization in the Mediates Pain and Anxiety Behaviors in the Rat. Physiol. Behav. 105 (2): 371-5.
  • Greenwood-Van Meerveld, B and Prodan, CI. (2012) Evidence of abnormal intestinal function related to hypocupremia in a rodent model. Neurogastroenterol. Motil. 24 (3):283-7, e112.doi
  • Hoffman JM, Onesmo B. Balemba, Johnson, A, Tyler K, Zhao Hong, Galligan J, Greenwood-Van Meerveld B, Mawe GM. (2012) Activation of colonic mucosal 5HT-4 receptors enhances propulsive motility and inhibits colonic hypersensitivity. Gastroenterology Gastroenterology 142(4):844-854.
  • Johnson, A.C., Tran L., Schulkin J, Greenwood-Van Meerveld, B. (2012) Importance of steroid receptor mediated mechanisms in the amygdala on visceral perception in a spontaneously anxious rat. Neurogastroenterol. Motil; 24(5): 479-86.
  • Camilleri M, Spiller R, Madsen, K Greenwood-Van Meerveld B and Verne N. (2012) Gut permeability in health and disease: an update. Neurogastroenterol. Motil. (Review) (in press)
  • Tran L, Wiskur B, Greenwood-Van Meerveld B (2012) The Role of the Bed Nucleus of the Stria Terminalis (BNST) in Stress-Induced Nociception. Am J Physiol. 302(11):G1301-9.
  • Tran, L, and Greenwood-Van Meerveld, B. (2012) Altered expression of glucocorticoid and CRF receptors in the rat central amygdala in response to elevated amygdala corticosterone. Behavioral Brain Research. 16;234 (2):380-385
  • Greenwood-Van Meerveld B, Tyler K, Mohammadi E, Pietra C. (2012) Efficacy of ipamorelin, a novel ghrelin agonist on gastric dysmotility in rodents. Journal of Exp. Pharmacology 149-155
  • Malykhina AP, Qin C, Lei Q, Pan XQ, Greenwood-Van Meerveld, B. Foreman RD (2013) Differential effects of intravesical resiniferatoxin on excitability of bladder spinal neurons upon colon-bladder cross-sensitization. Brain Research 1491:213-24.
  • Chaloner A, Greenwood-Van Meerveld, B. (2013) Comparison of age-dependent alterationsin pain and behavior between rats strains. Journal of the American Aging Association 35: 1-10
  • Tran, L, Chaloner A and Greenwood-Van Meerveld, B. (2013) Importance of Epigenetic Mechanisms in Stress-Induced Visceral Pain. Pyschoneuroendocrinology (in press)
  • Chaloner A, Greenwood-Van Meerveld B. (2013) Sexually Dimorphic Effects of Unpredictable Early Life Adversity on Visceral Sensitivity in a Rodent Model. J Pain (in press)