International Journal of Colorectal Disease

, Volume 15, Issue 4, pp 218–224

G protein levels and function as an objective measure of depression in patients with functional bowel disorders

  • Ami D. Sperber
  • Amit Y. Rotem
  • Alex Fich
  • Gregory Roitman
  • Gabriel Schreiber
  • Sofia Avissar
Original Article

DOI: 10.1007/s003840000240

Cite this article as:
Sperber, A., Rotem, A., Fich, A. et al. Int J Colorectal Dis (2000) 15: 218. doi:10.1007/s003840000240

Abstract.

Heterotrimeric G proteins play a pivotal role in postreceptor information transduction. These proteins have been implicated in the pathophysiology, diagnosis, and treatment of mood disorders and proposed as a state-dependent biochemical mood marker in mononuclear leukocytes. Irritable bowel syndrome (IBS) is associated with changes in mood, affecting patients' illness perceptions and behavior. We examined whether mononuclear leukocytes of patients with IBS have altered G protein measures. We undertook G protein functional measurements through agonist-enhanced [3H]Gpp(NH)p binding capacity and quantitative measures by immunoblot analysis using anti-Gα antibodies in mononuclear leukocytes obtained from 19 IBS patients (Rome criteria) and 19 healthy matched subjects. The study groups were similar in age, gender, and years of education. Mononuclear leukocyte functions of Gs (21.3±8.3%) and Gi (22.2±6.7%) proteins in IBS patients were similar to healthy subjects (24.8±4.7 and 25.2±4.0%, respectively). The relative immunoreactivities of the Gsα (98.9±10.2%) and the Giα (104.2±11.5%) subunit proteins in mononuclear leukocytes of IBS patients were also similar to those in healthy subjects. Two patients clinically diagnosed as depressed were detected by the G protein assay. The results lend objective support to the contention that major depression is not a causative factor in IBS, nor associated with its severity. The G protein assay may provide an objective biochemical tool for detecting depression in IBS, differentiating it from psychological distress that is commonly diagnosed by subjective tests.

Irritable bowel syndrome Depression G proteins Psychosocial factors Disease severity

Copyright information

© Springer-Verlag 2000

Authors and Affiliations

  • Ami D. Sperber
    • 1
  • Amit Y. Rotem
    • 1
  • Alex Fich
    • 1
  • Gregory Roitman
    • 2
  • Gabriel Schreiber
    • 2
  • Sofia Avissar
    • 3
  1. 1.Department of Gastroenterology, Soroka Medical Center, Faculty of the Health Sciences, Ben-Gurion University, Beer-Sheva 84105, Israel
  2. 2.Department of Psychiatry, Soroka Medical Center, Faculty of the Health Sciences, Ben-Gurion University, Beer-Sheva 84105, Israel
  3. 3.Department of Clinical Pharmacology, Soroka Medical Center, Faculty of the Health Sciences, Ben-Gurion University, P.O. Box 653, Beer-Sheva 84105, Israel