Behavioral Characteristics of 5-HT2C Receptor Knockout Mice: Locomotor activity, Anxiety-, and Fear Memory-related Behaviors.

Behavioral Characteristics of 5-HT2C Receptor Knockout Mice: Locomotor activity, Anxiety-, and Fear Memory-related Behaviors.
Behav Brain Res. 2019 Nov 28;:112394
Authors: Nebuka M, Ohmura Y, Izawa S, Bouchekioua Y, Nishitani N, Yoshida T, Yoshioka M
Abstract
Pharmacological studies have suggested that the serotonin 5-HT2C receptor is involved in locomotor activity, anxiety, and fear memory. However, the results of locomotor activity and anxiety in 5-HT2C receptor knockout mice have been mixed, and the effects of 5-HT2C receptor knockout on contextual fear memory have not yet been addressed. In the present study, we reconcile these inconsistent results by analyzing behavioral data in detail and by examining the effects of 5-HT2C receptor knockout on contextual fear memory. We demonstrated that the higher locomotor activity in 5-HT2C receptor knockout mice was observed only in the late phase of the test, indicating that the analyses in the previous study using the total locomotor activity would lead to variable results. Moreover, by analyzing mouse behavior in detail, we found that 5-HT2C receptor knockout mice displayed a hesitating attitude by staying in the central area as well as risk assessment behavior in the elevated plus-maze test. However, the time spent in the open arms was longer in 5-HT2C receptor knockout mice than in wild-type littermates when a zero-maze test lacking the central area was used. In the contextual fear con...

Source: Behavioural Brain Research - November 27, 2019 Category: Neurology Authors: Nebuka M, Ohmura Y, Izawa S, Bouchekioua Y, Nishitani N, Yoshida T, Yoshioka M Tags: Behav Brain Res Source Type: research