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 NaN 3 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 NaN 3 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.