Journal: bioRxiv

Article Title: The importance of M1 muscarinic receptor phosphorylation in learning and memory

doi: 10.64898/2026.03.23.713145

Figure Lengend Snippet: M1-WT mice were treated with varied doses of scopolamine (n=4-9) (A) , or subsequently 1.5 mg/kg scopolamine with varied doses of the M1-PAM VU846 (n=7-11) (B ), 30 mins prior to training in a fear conditioning paradigm and then returned to the same environment 24 hrs later for contextual memory retrieval whereby a reduced level of freezing indicates impaired memory. 2-way ANOVA with Dunnett’s post-hoc correction for multiple comparisons compared to vehicle, *p<0.05, **p<0.01, ***p<0.001, ns=not significant.

Article Snippet: Male mice were placed in a conditioning chamber (Stoelting ANY-maze Fear Conditioning System) for a period of 6.5 mins.

Techniques:

Journal: bioRxiv

Article Title: The importance of M1 muscarinic receptor phosphorylation in learning and memory

doi: 10.64898/2026.03.23.713145

Figure Lengend Snippet: M1-WT-HA (n=11-14) (A) , M1-KO (n=13-16) (B) or M1-PD-HA (n=11-14) (C) mice were treated with 1.5 mg/kg scopolamine +/-10 mg/kg VU846 30 mins prior to training in a fear conditioning paradigm. Mice were then returned to the same environment 24 hrs later for contextual memory retrieval whereby a reduced level of freezing indicates impaired memory. The response in vehicle treated animals across strains was also compared (D) . 2-way ANOVA with Tukey’s post-hoc correction for multiple comparisons, *p<0.05, ***p<0.001, ****p<0.0001, ns=not significant. (E ) Representative images of CA1 hippocampal region of HA-tagged M1-WT, M1-DREADD, M1-PD and M1-DREADD-PD stained with HA antibody demonstrating location of the receptor (green). Images at 40X magnification, scale bar = 50 µm

Article Snippet: Male mice were placed in a conditioning chamber (Stoelting ANY-maze Fear Conditioning System) for a period of 6.5 mins.

Techniques: Staining

Journal: bioRxiv

Article Title: The importance of M1 muscarinic receptor phosphorylation in learning and memory

doi: 10.64898/2026.03.23.713145

Figure Lengend Snippet: M1-WT-HA (n=11-14) (A) , M1-KO (n=13-16) (B) or M1-PD-HA (n=8-11) (C) mice were treated with 1.5 mg/kg scopolamine +/-10 mg/kg VU846 30 mins prior to training in a fear conditioning paradigm. Mice were then returned to a new environment the following day and presented with the tone for cued memory retrieval. 2-way ANOVA with Dunnett’s post-hoc correction for multiple comparisons to vehicle treatment, *p<0.05, ns=not significant. (D) The response in vehicle treated animals across strains was also compared. 2-way ANOVA with Tukey’s post-hoc correction for multiple comparisons, *p<0.05, ***p<0.001, ****p<0.0001, ns=not significant.

Article Snippet: Male mice were placed in a conditioning chamber (Stoelting ANY-maze Fear Conditioning System) for a period of 6.5 mins.

Techniques:

Journal: bioRxiv

Article Title: The importance of M1 muscarinic receptor phosphorylation in learning and memory

doi: 10.64898/2026.03.23.713145

Figure Lengend Snippet: (A) Male and female M1-WT-HA (n=11) and M1-PD (n=12) mice were treated with the M1-PAM VU846 30 mins prior to fear conditioning and returned to the chamber 24 hrs later for contextual memory retrieval. 2-way ANOVA ****p<0.0001 effect of strain, no significant effect of drug overall p=0.12, Bonferroni’s post-hoc correction for multiple comparisons between vehicle and VU846 for each strain, ns= not significant. (B & C) Male M1-DREADD mice were treated with 0.3 mg/kg of clozapine-N-oxide (CNO), an orthosteric agonist of the DREADD receptor, or vehicle (n=4-5 per group) 30 mins prior to training in a fear conditioning paradigm and then returned to the same environment 24 hrs later for contextual memory retrieval (B) or presentation of the tone in an altered environment 48 hrs later for cued memory retrieval (C) whereby a reduced level of freezing indicates impaired memory. (D) WT mice (n=7-9 per group) were also treated with 0.3 mg/kg CNO in a separate experiment demonstrating no effect of CNO. 2-way ANOVA with Dunnett’s post-hoc correction for multiple comparisons, ****p<0.0001, all other comparisons p>0.05.

Article Snippet: Male mice were placed in a conditioning chamber (Stoelting ANY-maze Fear Conditioning System) for a period of 6.5 mins.

Techniques:

Journal: bioRxiv

Article Title: The importance of M1 muscarinic receptor phosphorylation in learning and memory

doi: 10.64898/2026.03.23.713145

Figure Lengend Snippet: Male M1-DREADD mice were treated with 0.01 - 0.3 mg/kg of clozapine-N-oxide (CNO), an orthosteric agonist of the DREADD receptor, or vehicle (n=5-9 per group) 30 mins prior to training in a fear conditioning paradigm and then returned to the same environment 24 hrs later for contextual memory retrieval. Data presented as freezing level normalised to the highest freezing response. One way ANOVA with Bonferroni’s post hoc correction for multiple comparisons to vehicle treatment group *p<0.05. All other comparisons not significant.

Article Snippet: Male mice were placed in a conditioning chamber (Stoelting ANY-maze Fear Conditioning System) for a period of 6.5 mins.

Techniques:

Journal: bioRxiv

Article Title: Htr3a receptors control attenuation of fear responses by modulating the corticolimbic activity and synchronization

doi: 10.64898/2026.03.16.711072

Figure Lengend Snippet: Fear conditioning increases pip-induced local field potential (LFP) in control but not in Htr3a-KO during retrieval. A) Schema of the experimental setup for intracerebral recordings in head-fixed mice in the prelimbic cortex (PrL), infralimbic cortex (IL) and basolateral amygdala (BLA). B) Representative examples (1 mouse per condition) of pip-evoked potentials (1-100 Hz), z-normalized to 500ms pre-pip period, in WT and Htr3a-KO mice. Mean of all CS trains (420 pips, solid lines) ± SEM. C) Average pip-evoked LFP ± SEM across the 30 pips of each CS train in WT mice (n = 8; LFP data of 4/12 WT mice were excluded due to poor signal quality) in the PrL, IL, and BLA during habituation and retrieval days. Data are shown across the 14 CS trains (labelled t1 to t14) and were z-normalized to the 500 ms pre-pip baseline. In the PrL, there was a main effect of Days (p = 0.049) and of CS train (p = 0.002). In the IL, there was a main effect of days (p = 0.04), whereas the effect of CS train was not significant (p = 0.77). In the BLA, there was a main effect of days (p = 0.009) and of CS train (p < 0.001). Two-way ANOVA followed by Bonferroni post-hoc tests (*p < 0.05, **p < 0.01, ***p < 0.001). D) Pip-evoked responses in the Htr3a-KO mice (n = 8), no main effects were detected. E) Averaged LFP response of the first 3 CS during habituation and retrieval days, z-normalized to the 500ms pre-pip-onset in WT (main effect of Days: p =0.004, Bonferroni multiple comparison for PrL, IL and BLA: all p < 0.001) and Htr3a-KO (main effect of Days: p = 0.201). F) LFP responses of the first 3 CS in all mice during habituation (main effect of genotype: p = 0.275) and during retrieval (main effect of genotype: p = 0.038, Bonferroni multiple comparison for PrL: p = 0.489, IL: p = 0.097, BLA: *p = 0.043).

Article Snippet: On D5, mice underwent fear conditioning in a sound-attenuating conditioning chamber (17 × 17 × 25 cm; Ugo Basile, 46003), equipped with a grid floor of stainless-steel bars for shock delivery.

Techniques: Control, Comparison