Animals.
Male C57Bl6/J mice (Charles River Laboratories, France) aged between 60
and 90 days were used. To identify FSIs, mice expressing the fluorescent
tomato protein in parvalbumin neurons were generated by crossing
B6;129P2-Pvalbtm1(cre)Arbr/J strain with
B6.Cg-Gt(ROSA)26Sortm9(CAG-tdTomato)Hze/J strain from Jackson
Laboratory11The initial proposal planned to use wild type mice.
The use of transgenic mice expressing tomato protein in parvalbumin
neurons was introduced to identify the fast spiking interneurons in
cortical slices. This changes in the protocol received editorial
approval prior to data collection, on 9 Feb 2022.. All procedures
were in accordance with European Union recommendations for animal
experimentation (2010/63/UE). Mice were housed in groups of up to five
in standard laboratory cages and were kept on a 12-hour light/dark cycle
(at a constant temperature of 22°C) with food and water ad libitum.