Journal: Nature Communications

Article Title: Ventral hippocampus neurons encode meal-related memory

doi: 10.1038/s41467-025-59687-1

Figure Lengend Snippet: a Left: Diagram of a coronal section of the nucleus accumbens (ACB), adapted from the Brain Maps 4.0 structure of the rat brain . Middle: Representative photomicrographs of axonal green fluorescent protein (GFP) + expression in the ACB from ventral CA1 neurons active in the Fasted (Fasted GFP )( n = 5) or Fed (Fed GFP )( n = 4) state, relative to the anterior commissure (ac); scale bar 100 μm. Right: Average number of GFP + pixels in the ACB. b Left: Diagram of a coronal section of the lateral septum (LS), adapted from the Brain Maps 4.0 structure of the rat brain . Middle: Representative photomicrographs of axonal GFP + expression in the LS from ventral CA1 neurons active in the Fasted (Fasted GFP )( n = 5) or Fed (Fed GFP )( n = 4) state, relative to the lateral ventricle (lv); scale bar 100 μm. Right: Average number of GFP + pixels in the LS. c Left: Diagram of a coronal section of the lateral hypothalamic area (LHA), adapted from the Brain Maps 4.0 structure of the rat brain . Middle: Representative photomicrographs of axonal GFP + expression in the LHA from ventral CA1 neurons active in the Fasted (Fasted GFP )( n = 5) or Fed (Fed GFP )( n = 4) state, relative to the fornix (fx) and 3rd ventricle (3 v); scale bar 100 μm. Right: Average number of GFP + pixels in the LHA ( p value = 0.0159). d Left: Representative photomicrograph of retrograde GFP viral expression in the LS, relative to the lv; scale bar 200 μm. Right: Representative photomicrograph of retrograde mCherry viral expression in the LHA, relative to the fx; scale bar 200 μm. e Average number of LS (GFP)( n = 4) and LHA (mCherry)( n = 4)-projecting neurons labeled in the CA1v. f Average percentage of CA1v neurons sending axonal projections to both the LS (GFP)( n = 4) and LHA (mCherry)( n = 4). g Average percentage of LS (GFP)( n = 4) and LHA (mCherry)( n = 4)-projecting CA1v neurons expressing cFos in the Fed state ( p value < 0.0001). h Representative photomicrograph of fluorescent in situ hybridization for Fos (cyan) in LS (GFP) and LHA (mCherry)-projecting neurons of the CA1v, relative to the alveus (alv); scale bar 100 μm. Data are presented as mean ± SEM. For a – c and d – g , two-tailed unpaired t-test; * p < 0.05, **** p < 0.0001. No symbol indicates lack of significance.

Article Snippet: The same rats also received a unilateral injection (200nL) of a retrograde AAV expressing mCherry (AAVrg-hSyn-mCherry; Addgene viral prep # 11472-AAVrg gifted by Karl Deisseroth) into the LHA at the following coordinates: −2.9 mm AP, + or −1.1 mm ML, and −8.6 mm DV (all defined at bregma).

Techniques: Expressing, Labeling, In Situ Hybridization, Two Tailed Test

Journal: Nature Communications

Article Title: Ventral hippocampus neurons encode meal-related memory

doi: 10.1038/s41467-025-59687-1

Figure Lengend Snippet: a Diagram of viral approach for expression of GCaMP7s in ventral CA1 neurons projecting to the lateral hypothalamic area and implantation of the optic fiber, adapted from the Brain Maps 4.0 structure of the rat brain . b Representative photomicrograph of GCaMP7s expression for placement validation of viral injections, relative to the alveus (alv); scale bar 100 μm (representative pattern was observed in all animals used in the analyses, n = 3). c Representative trace of a single animal of the increase in calcium-dependent activity during the interbout intervals (purple) in ventral hippocampus neurons projecting to the lateral hypothalamic area. d Average change in z-score for fluorescence over the course of an eating bout versus during an interbout interval ( n = 3 animals)( p value = 0.0165). e Diagram of viral approach for expression of hM4Di receptors in ventral CA1 neurons projecting to the lateral hypothalamic area and administration of vehicle (VEH) or clozapine-N-oxyde (CNO) through a lateral ventricle (LV) cannula, adapted from the Brain Maps 4.0 structure of the rat brain . f Representative photomicrograph of mCherry expression for placement validation of viral injections, relative to the alveus (alv); scale bar 100 μm (representative pattern was observed in all animals used in the analyses, n = 10). g Average number of errors and h latency to find the food during training for the foraging-related spatial memory task in animals assigned to VEH ( n = 6) or CNO ( n = 4) groups. i Performance index during the probe for the foraging-related spatial memory task, 1 h following LV administration of VEH ( n = 6) or CNO ( n = 4)(Group comparison p value = 0.0024; p value for 1-sample t-test = 0.0014 for VEH group). Data are presented as mean ± SEM. For d , two-tailed paired t-test. For g – h , two-way ANOVA. For i , two-tailed unpaired t-test ( n = 4–6/group); * p < 0.05, ** p < 0.01. For i , one-sample t-test, different from chance set at 0.1667; ## p < 0.01. No symbol indicates lack of significance.

Article Snippet: The same rats also received a unilateral injection (200nL) of a retrograde AAV expressing mCherry (AAVrg-hSyn-mCherry; Addgene viral prep # 11472-AAVrg gifted by Karl Deisseroth) into the LHA at the following coordinates: −2.9 mm AP, + or −1.1 mm ML, and −8.6 mm DV (all defined at bregma).

Techniques: Expressing, Biomarker Discovery, Activity Assay, Fluorescence, Comparison, Two Tailed Test