title: Diversity and overlap of parvalbumin and somatostatin expressing interneurons in mouse presubiculum.
abstract: The presubiculum, located between hippocampus and entorhinal cortex, plays a fundamental role in representing spatial information, notably head direction. Little is known about GABAergic interneurons of this region. Here, we used three transgenic mouse lines, Pvalb-Cre, Sst-Cre, and X98, to examine distinct interneurons labeled with tdTomato or green fluorescent protein. The distribution of interneurons in presubicular lamina for each animal line was compared to that in the GAD67-GFP knock-in animal line. Labeling was specific in the Pvalb-Cre line with 87% of labeled interneurons immunopositive for parvalbumin (PV). Immunostaining for somatostatin (SOM) revealed good specificity in the X98 line with 89% of fluorescent cells, but a lesser specificity in Sst-Cre animals where only 71% of labeled cells were immunopositive. A minority of ∼6% of interneurons co-expressed PV and SOM in the presubiculum of Sst-Cre animals. The electrophysiological and morphological properties of fluorescent interneurons from Pvalb-Cre, Sst-Cre, and X98 mice differed. Distinct physiological groups of presubicular interneurons were resolved by unsupervised cluster analysis of parameters describing passive properties, firing patterns and AP shapes. One group consisted of SOM-positive, Martinotti type neurons with a low firing threshold (cluster 1). Fast spiking basket cells, mainly from the Pvalb-Cre line, formed a distinct group (cluster 3). Another group (cluster 2) contained interneurons of intermediate electrical properties and basket-cell like morphologies. These labeled neurons were recorded from both Sst-Cre and Pvalb-Cre animals. Thus, our results reveal a wide variation in anatomical and physiological properties for these interneurons, a real overlap of interneurons immuno-positive for both PV and SOM as well as an off-target recombination in the Sst-Cre line, possibly linked to maternal cre inheritance.
authors.affiliation: Institut du Cerveau et de la Moelle Epinière, Sorbonne Universités, UPMC Université Paris 06 UM 75, CHU Pitié-Salpêtrière INSERM U1127, CNRS UMR7225 Paris, France.
authors.forename: Mérie
authors.initials: M
authors.lastname: Nassar
authors.affiliation: Institut du Cerveau et de la Moelle Epinière, Sorbonne Universités, UPMC Université Paris 06 UM 75, CHU Pitié-Salpêtrière INSERM U1127, CNRS UMR7225 Paris, France.
authors.forename: Jean
authors.initials: J
authors.lastname: Simonnet
authors.affiliation: Institut du Cerveau et de la Moelle Epinière, Sorbonne Universités, UPMC Université Paris 06 UM 75, CHU Pitié-Salpêtrière INSERM U1127, CNRS UMR7225 Paris, France.
authors.forename: Roxanne
authors.initials: R
authors.lastname: Lofredi
authors.affiliation: Neuroscience Paris Seine Paris, Sorbonne Universités, UPMC Université Paris 06 UM CR 18, CNRS UMR 8246, INSERM U1130 Paris, France.
authors.forename: Ivan
authors.initials: I
authors.lastname: Cohen
authors.affiliation: Institut du Cerveau et de la Moelle Epinière, Sorbonne Universités, UPMC Université Paris 06 UM 75, CHU Pitié-Salpêtrière INSERM U1127, CNRS UMR7225 Paris, France.
authors.forename: Etienne
authors.initials: E
authors.lastname: Savary
authors.affiliation: Department of Genetic and Behavioral Neuroscience, Gunma University Graduate School of Medicine Maebashi, Japan ; Japan Science and Technology Agency Tokyo, Japan.
authors.forename: Yuchio
authors.initials: Y
authors.lastname: Yanagawa
authors.affiliation: Institut du Cerveau et de la Moelle Epinière, Sorbonne Universités, UPMC Université Paris 06 UM 75, CHU Pitié-Salpêtrière INSERM U1127, CNRS UMR7225 Paris, France.
authors.forename: Richard
authors.initials: R
authors.lastname: Miles
authors.affiliation: Institut du Cerveau et de la Moelle Epinière, Sorbonne Universités, UPMC Université Paris 06 UM 75, CHU Pitié-Salpêtrière INSERM U1127, CNRS UMR7225 Paris, France.
authors.forename: Desdemona
authors.initials: D
authors.lastname: Fricker
mesh_terms: D000818:Animals; D016000:Cluster Analysis; D005260:Female; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional; D007150:Immunohistochemistry; D007395:Interneurons / Q000166:cytology* / Q000378:metabolism; D008297:Male; D051379:Mice; D008822:Mice, Transgenic; D020534:Parahippocampal Gyrus / Q000166:cytology* / Q000502:physiology*; D010320:Parvalbumins / Q000096:biosynthesis; D018408:Patch-Clamp Techniques; D013004:Somatostatin / Q000096:biosynthesis
chemical_list: D010320:Parvalbumins; D013004:Somatostatin
keywords: excitability; head direction; inhibition; morphology; postsubiculum