The locus coeruleus influences behavior by coordinating effective integration of fear memories and sensory input
Fig 8
Short-term plasticity of the dmPFC-LC connections enables the CS generalization during threat memory retrieval.
(A) NE signals in the dmPFC elicited by 10 s CS+ or 2 s CS+/28 s CS−. Scale bars, 0.5% ΔF/F and 10 s. N = 5 mice. Insert: AUC of ΔF/F of dmPFC NE signals. (B) LC Ca2+ signals elicited by 2 s CS+ or 2 s CS+/28 s CS−. Scale bars, 2% ΔF/F and 10 s. N = 7 mice. Insert: AUC of ΔF/F of Ca2+ signals. Two-tailed unpaired t test, 2 s CS+/28 s CS− vs. 2 s CS+, P < 0.05. (C) Ca2+ signals in the LC TH+ neurons elicited by 2 s CS+ and 2 s CS+/28 s CS−. Scale bars, 2% ΔF/F and 10 s. N = 7 mice. Insert: AUC of ΔF/F of Ca2+ signals. Two-tailed unpaired t test, 2 s CS+/28 s CS− vs. 2 s CS+, P < 0.001. (D) Ca2+ signals elicited by 2 s CS+/28 s CS− and 2 s CS+ in the LC neurons receiving dmPFC projections. N = 7 mice, Two-tailed unpaired t test, 2 s CS+/28 s CS− vs. 2 s CS+, P < 0.01. (E) Ca2+ signals elicited by 2 s CS+/28 s CS− and 2 s CS+ in the LC neurons projecting to dmPFC. N = 7 mice, Two-tailed unpaired t test, 2 s CS+/28 s CS− vs. 2 s CS+, P < 0.01. (F) (Left) Sites of virus injections and optical fiber implantation. (Right) Freezing levels elicited by 30 s CS+, 2 s blue light stimulation followed by 28 s CS−. N = 5 mice, each group. (G) (Left) (Top) Experimental procedure for opto-stimulation. (Bottom) Normalized sEPSC frequency in the LC neurons to the sEPSCs during baseline period (period A). (Right) Representative traces of recorded EPSCs in the LC neurons during baseline (TeA stimulation only), during TeA + PFC stim and after stimulation (TeA stimulation only). Scale bars, 2 s and 20 pA. N = 6 cells/2 mice. (H) (Left) (Top) Experimental procedure for opto-stimulation. (Bottom) Normalized sEPSC frequency in the LC neurons to the sEPSC during baseline period (period A). (Right) Representative traces of recorded EPSCs in the LC neurons to opto-stimulation of TeA inputs, for the same durations as in (G). Scale bars, 2 s and 20 pA. N = 9 cells/2 mice. Numerical data can be found in S1 Data.