New mouse model for inducing and evaluating unilateral vestibular deafferentation syndrome

Reduced Balance Restoration Capacities Following Unilateral Vestibular Insult in Elderly Mice

“…Acute vestibular syndrome (AVS) was induced in young adult and elderly mice via trans-tympanic administration of kainate (TTK) according to the method detailed previously ( 28 ). A schematic representation of the experimental design is shown in Figure 1 .…”

“…The behavioral evaluations were performed at 8 times points: baseline (BL), 4 h (4 h), 24 h (24 h), 48 h (48 h), 72 h (72 h), 1 week (1 W), 2 weeks (2 W) and 3 weeks (3 W) as shown in Figure 1 . Except for the number of rearings and for the swim duration, the other items were quantified on a scale from 0 (mouse exhibited no trouble at all) to 3 (value that represents the highest degree of vestibular alteration), as previously described ( 26 – 28 , 34 ) and based on a previous paper that showed the utility of the behaviors evaluated ( 35 ). All measurements were performed systemically by the same experimenter both directly and offline through analyze of the videos recorded for each experiment.…”

“…To assess their ability to maintain their balance in water and to monitor the quality of their swimming, the mice were put in the pool for 30 s. Evaluation of the swim quality was performed using the specific behavior grid detailed previously ( 28 ). We also paid attention to whether the mice were tumbling or not in the water.…”

“…This referred to the time spent swimming before we took the mouse out of the water. Detailed descriptions of all these behavioral parameters were provided previously ( 28 ).…”

“…It also highlighted the ability of rodents to quickly restore their balance and posture, based on a robust propensity of peripheral vestibular synapses to spontaneously repair following kainate-induced deafferentation ( 27 ). A recent adaptation of the mouse TTK model and the development of more precise monitoring of both the specific signs of vestibular function and the general behavioral alterations provided the opportunity to better follow the temporal evolution of several specific symptoms of AVS, while better appreciating the different phases that compose this syndrome ( 28 ). It also brought insights into our understanding on how AVS develops and how it affects global behavior.…”