STN inhibition

The behavioral effects of subthalamic nucleus (STN) inhibition in a DD mouse.

Brief description:
We inhibited the subthalamic nucleus (STN) of a dopamine-deficient (DD) mice by reverse dialysis of an mGluR5 receptor antagonist. Although DD mice are profoundly hypoactive and hypophagic in the absence of brain dopamine, inhibition of the STN resulted in almost immediate onset of locomotion, and feeding. This video begins approximately 1.5 minutes after the drug has reached the STN. Behavioral effects of the drug during the first minute included whisker movements and sniffing. At the beginning of this sequence, the mouse began to move voluntarily for the first time in hours. Note the characteristic Parkinsonian, elongated hindlimb gait of the DD mouse is maintained when he walks. The STN inhibition was maintained overnight, and by morning the DD mouse had eaten enough to have gained weight, despite having received no DA-replacement for over 36 hours.

The video above begins approximately 3 minutes after the drug has reached the STN. The mouse has already begun to explore the cage, and to groom. At the beginning of this sequence, the experimenter placed several pellets of food into the cage.