Anesthetic-like effects of ketamine in C. elegans

Transparency of C. elegans enables microscopic in vivo imaging of cellular processes, but immobilization is required due to high locomotor activity. Preservative NaN3 is commonly used for this, but is associated with oxidative stress and toxicity. Here, anesthetic-like effects of dissociate anesthetic ketamine in C. elegans are presented using video recordings and infrared-based automated activity tracking. Ketamine caused a reversible blockade of locomotion at a similar concentration (20-50 mM) at which NaN3 produces paralysis. Moreover, the recovery rate was remarkably high, and short-term ketamine treatment did not show signs of SKN-1 activation, a marker of the stress response.