Skip to main content
Fig. 4 | Journal of Biomedical Science

Fig. 4

From: A dorsal CA2 to ventral CA1 circuit contributes to oxytocinergic modulation of long-term social recognition memory

Fig. 4

Pharmacological antagonism of OXTR in dCA2 blocks chemogenetic enhancement of long-term SRM. A Schematic representation of the experimental design. B Schematic representation of viral injection and CNO administration. Three weeks after stereotaxic injection of AAV5-mOXT-hM3D(Gq)-mCherry into the PVN, mice were subjected to three-chamber paradigm test and long-term SRM retention was tested 7 days after the initial interaction. Mice were bilaterally administered of vehicle (Veh) or an OXTR antagonist L-368,899 into dCA2 10 min before CNO injection, followed by three-chamber paradigm test 20 min after CNO injection. Representative images showing the co-expression of hM3D(Gq)-mCherry and OXT immunoreactivity in the PVN. mCherry signals of axonal projections were observed in dCA2. Scale bar represents 50 μm. C Top, schematic representation of the three-chamber sociability test. Bottom left, time spent by the subject mouse in sniffing directed at the wire cage containing the juvenile stimulus mouse or the empty wire cage. hM3D(Gq)/CNO/Veh and hM3D(Gq)/CNO/L-368,899 subject mice spent significantly more time interacting with the wire cage containing the juvenile stimulus mouse than the empty wire cage. Bottom right, discrimination index (stimulus minus empty) was similar between groups in the sociability test. D Top, schematic representation of the three-chamber social novelty preference test. Bottom left, time spent by the subject mouse in sniffing directed at the wire cage containing a familiar mouse or a novel 1 mouse, 10 min after the sociability test. hM3D(Gq)/CNO/Veh and hM3D(Gq)/CNO/L-368,899 subject mice spent significantly more time sniffing the cage containing the novel mouse than the familiar mouse. Bottom right, discrimination index (novel 1 minus familiar) was comparable between groups in the social novelty preference test. E Top, schematic representation of the three-chamber long-term SRM test. Bottom, time spent by the subject mouse in sniffing directed at the wire cage containing a familiar mouse or a novel 2 mouse, 7 days after the initial interaction. hM3D(Gq)/CNO/Veh, but not hM3D(Gq)/CNO/L-368,899, subject mice spent significantly more time sniffing the cage containing the novel mouse than the familiar mouse. Bottom right, discrimination index (novel 2 minus familiar) of hM3D(Gq)/CNO/Veh subject mice was significantly higher than that of hM3D(Gq)/CNO/L-368,899 subject mice in 7-day long-term SRM test. The total number of animal examined is indicated by n in parenthesis. Error bars represent the SEM; *P < 0.05, **P < 0.01, ***P < 0.001

Back to article page