Engaging homeostatic plasticity to treat depression

Area of Science:

• Neuroscience
• Pharmacology
• Molecular Biology

Background:

• Major Depressive Disorder (MDD) is complex, hindering generalized treatment.
• N-methyl-D-aspartate receptor (NMDAR) antagonists offer rapid antidepressant effects, providing insights into treatment mechanisms.

Purpose of the Study:

• To review the mechanisms of NMDAR antagonists as rapid-acting antidepressants.
• To explore how these antagonists engage homeostatic mechanisms for neural self-correction.

Main Methods:

• Review of critical studies on NMDAR antagonist action.
• Analysis of molecular and circuit-level effects of antidepressants.
• Examination of the role of mTORC1 and GABA B receptors.

Main Results:

• NMDAR antagonists induce rapid antidepressant effects by activating protein-synthesis-dependent homeostatic mechanisms.
• Synaptogenesis and increased excitatory drive are key to symptom relief.
• A shift in gamma-aminobutyric acid receptor B (GABA B R) from inhibitory to excitatory is crucial for mTORC1-dependent translation.

Conclusions:

• NMDAR antagonists promote neural self-correction through synaptogenesis and restored excitatory connections.
• The mTORC1 pathway and GABA B R function are critical mediators of rapid antidepressant action.
• Understanding these mechanisms may resolve discrepancies in antidepressant action and local homeostatic regulation.