Alpha2C-adrenoceptor overexpression disrupts execution of spatial and non-spatial search patterns
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Updated: Mar 1, 2026
An Appetitive Spatial Working Memory Task for Mice in a Semi-Automated 8-Arm Radial Maze, Reducing Fearful Memory Association in the Maze
Published on: July 29, 2025
M Björklund1, J Sirviö, J Sallinen
1Department of Neurology and Neuroscience, University of Kuopio, Finland.
Abstract:
We investigated the role of alpha2C-adrenoceptors in the modulation of spatial and non-spatial navigation behaviour. Alpha2C-adrenoceptor overexpressing mice developed an ineffective thigmotaxic search pattern characterized by swimming close to the pool walls during both spatial and non-spatial water maze training. A subtype-non-selective alpha2-adrenoceptor antagonist, atipamezole (1000 microg/kg, s.c.), fully reversed this impairment in their search strategy. Withdrawal of atipamezole at the end of spatial training resulted in an immediate disruption of the search pattern in alpha2C-adrenoceptor overexpressing mice. The swimming pattern of alpha2C-adrenoceptor overexpressing mice during a five day free swimming period was normal, when no cognitive component was required. Diazepam (0.3 and 1.0 mg/kg, i.p.), neither improved the accuracy in finding the platform nor decreased thigmotaxis. These results suggest that alpha2C-adrenoceptors may modulate the execution of complex navigation patterns.
Insights
Alpha2C-adrenoceptors influence navigation strategies. Overexpressing these receptors led to ineffective search patterns, which were reversed by an alpha2-adrenoceptor antagonist, suggesting their role in complex navigation.
Area of Science:
- Neuroscience
- Behavioral Pharmacology
- Neurobiology
Background:
- Adrenoceptors play crucial roles in modulating various physiological and behavioral processes.
- Alpha2C-adrenoceptors are implicated in central nervous system functions, but their specific role in navigation remains underexplored.
Purpose of the Study:
- To investigate the role of alpha2C-adrenoceptors in modulating spatial and non-spatial navigation behavior.
- To determine the effects of alpha2C-adrenoceptor manipulation on search strategies in a water maze task.
Main Methods:
- Utilized alpha2C-adrenoceptor overexpressing mice in spatial and non-spatial water maze tasks.
- Administered a subtype-non-selective alpha2-adrenoceptor antagonist (atipamezole) to assess its effects on navigation.
- Observed swimming patterns and platform finding accuracy.
- Tested the effects of diazepam on navigation behavior.
Main Results:
- Alpha2C-adrenoceptor overexpressing mice exhibited an ineffective thigmotaxic search pattern, swimming along pool walls.
- Atipamezole administration fully reversed the impaired search strategy in these mice.
- Disruption of the search pattern occurred immediately upon atipamezole withdrawal.
- Normal swimming patterns were observed in the absence of cognitive demands.
- Diazepam did not improve navigation accuracy or reduce thigmotaxis.
Conclusions:
- Alpha2C-adrenoceptors significantly modulate the execution of complex navigation patterns.
- Targeting alpha2C-adrenoceptors may offer a potential therapeutic avenue for navigation-related behavioral impairments.
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