Dynamics of ECT normalization of low G protein function and immunoreactivity in mononuclear leukocytes of patients with major depression.

Abstract

OBJECTIVE:

Heterotrimeric G proteins were previously implicated in the biochemical mechanisms underlying the pathophysiology and treatment of mood disorders. Low function and immunoreactivity of G proteins were observed in patients with major depression. In the present study the authors evaluated the effects of ECT on the low measures of G proteins in patients with major depression.

METHOD:

Repeated G protein measurements in mononuclear leukocytes of 10 patients with major depression were made. Each patient was examined while untreated and after successive sessions of ECT; 14 normal subjects were also studied. G protein function was evaluated through beta-adrenergic- and muscarinic-agonist-enhanced guanine nucleotide binding capacity, substantiated by quantitative measures of G proteins through immunoblot analyses using polyclonal antibodies against Gs alpha, Gi alpha, and G beta proteins.

RESULTS:

Mononuclear leukocytes of patients with depression showed immunoreactive levels of Gs alpha and Gi alpha that were significantly lower than those of normal subjects; the depressed patients also had markedly hypofunctional Gs and Gi. The low levels of G protein function and immunoreactivity were alleviated by ECT. Repeated measurements in the same patients after successive ECT sessions showed that the normalization of G protein measures preceded, and thus predicted, clinical improvement. The function and quantity of Gs and Gi proteins in patients given ECT were significantly correlated.

CONCLUSIONS:

These findings support the implication of G proteins in the pathophysiology and treatment of mood disorders. G protein measurements in patients with depression may potentially serve not only as a biochemical marker for affective state but also for biochemical prediction and evaluation of responses to ECT.

• Authors: S Avissar, Y Nechamkin, G Roitman, G Schreiber
• Journal: The American journal of psychiatry (Am J Psychiatry) Vol. 155 Issue 5 Pg. 666-71 (May 1998) ISSN: 0002-953X [Print] United States
• PMID: 9585719 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Biomarkers
• Guanylyl Imidodiphosphate
• Carbachol
• GTP-Binding Proteins
• Isoproterenol

Topics

• Biomarkers
• Carbachol (pharmacology)
• Depressive Disorder (immunology, physiopathology, therapy)
• Electroconvulsive Therapy
• GTP-Binding Proteins (analysis, immunology, physiology)
• Guanylyl Imidodiphosphate (metabolism)
• Humans
• Immunoblotting
• Isoproterenol (pharmacology)
• Leukocytes, Mononuclear (chemistry, immunology)