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Cav3.2 T-type calcium channel-dependent gene expression after retrieval of context-associated memory (right hippocampus)

ABSTRACT: Among all voltage-gated calcium channels, the T-type Ca2+ channels encoded by the Cav3 genes are highly expressed in the hippocampus, which is associated with contextual, temporal and spatial learning and memory. However, the specific involvement of the Cav3.2 T-type Ca2+ channel in these hippocampus-dependent types of learning and memory remains unclear. To investigate the functional role of the 1H channel in learning and memory, we subjected Cav3.2 homozygous, heterozygous knockout and their wild-type littermates to hippocampus-dependent behavioral tasks, including trace fear conditioning (TFC), the Morris water-maze and passive avoidance. The Cav3.2-/- mice performed normally in the Morris water-maze and auditory trace fear conditioning tasks but were impaired in the context-cued trace fear conditioning, step-down and step-through passive avoidance tasks. Furthermore, long-term potentiation (LTP) could be induced for 180 minutes in hippocampal slices of WTs and Cav3.2+/- mice, whereas LTP persisted for only 120 minutes in Cav3.2-/- mice. To determine whether the hippocampal formation is responsible for the impaired behavioral phenotypes , we next performed experiments locally knock down function of the Cav3.2 T-type Ca2+ channel in the hippocampus. Wild-type mice infused with mibefradil exhibited similar behaviors as homozygous knockouts. Finally, microarray analyses indicated that Cav3.2-/- and WT mice presented distinct hippocampal transcriptome profiles. Taken together, our results demonstrate that retrieval of context-associated memory is dependent on the Cav3.2 T-type Ca2+ channel.

ORGANISM(S): Mus musculus

PROVIDER: GSE30845 | GEO | 2013/02/28

SECONDARY ACCESSION(S): PRJNA154557

REPOSITORIES: GEO

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Cav3.2 T-type calcium channel-dependent gene expression after retrieval of context-associated memory (right hippocampus)

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