Fig. 5: Chemogenetic inhibition of PSTN CR neurons decreases wakefulness and exploratory behaviors.
From: Parasubthalamic calretinin neurons modulate wakefulness associated with exploration in male mice
a Diagram of bilateral viral infection area of AAV-hSyn-DIO-hM4Di-mCherry in the PSTN. b Representative photomicrographs of the PSTN depicting mCherry (red), c-Fos (green), and merge (yellow) images of PSTN-mCherry and PSTN-hM4Di mice after administration of CNO. CNO decreases c-Fos expression in hM4Di-expressing neurons in the PSTN. Scale bar: 50 µm. c Representative voltage traces recorded from an mCherry-expressing neuron and an hM4Di-expressing neuron during the application of CNO, which reduced the firing rate in a patched hM4Di-expressing neuron. d Examples of relative EEG power, EEG/EMG traces, and hypnograms over 4 h following CNO injection of PSTN-mCherry or PSTN-hM4Di mice at 21:00. e Time course changes in wakefulness, NREM sleep, and REM sleep after administration of CNO to PSTN-mCherry or PSTN-hM4Di mice (mCherry group: n = 5, hM4Di group: n = 7; Two-way ANOVA; Wake: F1,10 = 11.73, P = 0.0065; NREM: F1,10 = 12.53, P = 0.0054; REM: F1,10 = 2.22, P = 0.1671). f Total time spent in each stage for 2 h after CNO injection of PSTN-mCherry or PSTN-hM4Di mice (mCherry group: n = 5, hM4Di group: n = 7; unpaired two-sided t-test; Wake: t10 = 3.835, P = 0.0033; NREM: t10 = 3.821, P = 0.0034; REM: t10 = 1.326, P = 0.2142). g EEG power density of wakefulness and NREM sleep during the 2 h after CNO injection of PSTN-mCherry or PSTN-hM4Di mice (n = 7, Two-way ANOVA; not statistically significant). h Quantification of behaviors observed in mice during 1 h following 9 pm CNO injection or saline injection (n = 7, paired two-sided t-test; sniff: t6 = 3.077, P = 0.02176; rear: t6 = 2.853, P = 0.02906; walk: t6 = 3.37, P = 0.01504; groom: t6 = 2.335, P = 0.05824; drink: t6 = 1.419, P = 0.2056; eat: t6 = 0.08934, P = 0.9317). Chemogenetic inhibition of PSTN CR neurons decreased sniffing, rearing, and walking behaviors. i, j There was no significant change in behavior in the OFT and light-dark box test after inhibition of PSTN CR neurons (n = 7, unpaired two-sided t-test). Data represent mean ± SEM, *P < 0.05, **P < 0.01.
