A new method to model electroconvulsive therapy in rats with increased construct validity and enhanced translational...

Area of Science:

• Neuroscience
• Psychiatry
• Pharmacology

Background:

• Electroconvulsive therapy (ECT) is highly effective for major depressive disorder (MDD), particularly treatment-resistant cases.
• Understanding ECT's mechanisms is crucial, and rodent electroconvulsive stimulation (ECS) models are used for this.
• Current rodent ECS models lack construct validity due to differences in electrode placement compared to human ECT.

Purpose of the Study:

• To develop a more valid rodent model of ECT by using cortical electrodes.
• To compare the efficacy and safety of cortical ECS versus auricular ECS in rats.

Main Methods:

• ECS was administered to rats using screw electrodes placed over the motor cortex (cortical ECS).
• The induced seizures were compared to human ECT.
• The antidepressant-like effect was assessed using the forced swim test.
• General health and behavioral signs of distress were monitored during auricular ECS.

Main Results:

• Cortical ECS reliably induced seizures comparable to human ECT.
• Cortical ECS demonstrated greater efficacy in reducing immobility in the forced swim test than auricular ECS.
• Auricular ECS negatively impacted rat health and induced fear responses.

Conclusions:

• Cortical ECS in rats offers a more valid model for studying ECT mechanisms.
• Auricular ECS is not a suitable model due to adverse effects and lower efficacy.
• This improved model enhances the translational value of preclinical ECT research.