Hippocampal inputs engage CCK+ interneurons to mediate endocannabinoid-modulated feed-forward inhibition in the prefrontal cortex
- Center for Neural Science, New York University, United States
- Stanley Center for Psychiatric Research, Broad Institute of Massachusetts Institute of Technology and Harvard, United States
- Department of Neurobiology, Harvard Medical School, United States
Figures
Figure 1 with 1 supplement
vHPC-evoked feed-forward inhibition and CCK+ interneurons.
(A) Schematic for injections of AAV-ChR2-EYFP into vHPC and CTB-647 into cPFC. (B) Left, Confocal image of vHPC axons (blue) in IL PFC. Scale bar = 100 µm. Right, Confocal image of biocytin-filled …
Figure 1—figure supplement 1
Anatomy of CCK+ and other interneurons in L5 IL PFC.
(A) Co-labeling of GFP-expressing CCK+ interneurons (purple) with PV (blue) and SOM (green). Immunohistochemistry of GFP and either PV (top) or SOM (bottom) in PFC slices from CCK-Cre animals …
Figure 2
vHPC inputs differentially engage PV+, SOM+, and CCK+ interneurons.
(A) Left, Average vHPC-evoked EPSCs at pairs of L5 IT (gray) and CCK+ (purple) cells in IL PFC. Blue arrow = light pulse. Middle, Summary of EPSC amplitudes. Right, Summary of CCK+/IT EPSC amplitude …
Figure 3
vHPC inputs drive interneurons with distinct temporal dynamics.
(A) Left, Average vHPC-evoked EPSCs at CCK+ interneurons, recorded in voltage-clamp at −65 mV (5 pulses at 20 Hz). Blue arrows = light pulses (n = 6 cells, 3 animals). Middle, For PV+ interneurons …
Figure 4 with 1 supplement
CCK+ interneurons make connections onto pyramidal cells.
(A) Left, Injections of AAV-Dlx-Flex-ChR2 into the PFC of CCK-Cre animals. Middle, Example AP traces from a ChR2-expressing CCK+ interneuron, stimulated with 2 ms light pulses at 20 Hz, showing 5 …
Figure 4—figure supplement 1
Subcellular targeting of CCK+ interneurons to IT and PT cells in L5 IL PFC.
(A) Left, Schematic for examining the subcellular targeting of CCK+ interneurons to IL L5 IT cells. 75 µm light pixels were delivered at 1 Hz using a pseudo-random 10 × 10 gridded pattern, yielding …
Figure 5 with 3 supplements
Prominent DSI of CCK+ inputs onto IT cells.
(A) Injection schematic of CTB-647 into cPFC and red retrobeads (RB) into PAG, along with AAV-Dlx-Flex-ChR2 into PFC of CCK-Cre mice. (B) Experimental procedure for depolarization-induced …
Figure 5—figure supplement 1
Time course of CCK inputs to IT cells during DSI protocol.
(A) Schematic for examining the time course of DSI. An IT cell was held at −50 mV and 2 ms lights stimulations were delivered at 5 s intervals to establish the baseline input strengths. A brief 5 s …
Figure 5—figure supplement 2
Minimal DSI at PV+ or SOM+ interneuron connections onto IT cells.
(A) Injection schematics of CTB-647 into cPFC and AAV-Flex-ChR2 in PFC of PV-Cre mice. (B) Left, Average PV+ inputs onto IT cells, evoked by 5 pulses at 20 Hz, before (black), immediately after the …
Figure 5—figure supplement 3
Suppression of inhibition induced by IT cell firing.
(A) Experimental procedure for suppression of inhibition induced by IT cell firing. The procedure was similar to the voltage-clamp DSI protocol shown in Figure 5. IT cells were injected with holding …
Figure 6 with 1 supplement
Cell-type specific modulation by CB1 receptors.
(A) Left, Schematic of recordings from IT cells in L5 of IL PFC. Middle, Average CCK+-evoked IPSCs at IT cells at baseline (black), 10 min after wash-in of 1 µM WIN 55,212–2 (red), and 15 min after …
Figure 6—figure supplement 1
The effect of AM-251 on CCK+ inputs to IL L5 IT cells.
(A) Left, Recording schematic. Right, Average CCK+-evoked IPSCs at IT cells at baseline (black) and 10 min after wash-in of 10 µM AM-251 (red). Purple arrow = 2 ms LED stimulation. (B) Summary of …
Figure 7
vHPC-evoked feed-forward inhibition at IT cells undergoes DSI.
(A) Injection schematic, showing CTB-647 in cPFC, red retrobeads (RB) in PAG, along with AAV-ChR2-EYFP in vHPC. (B) Left, Average vHPC-evoked EPSCs and IPSCs at IT cells in L5 IL PFC, before …
Author response image 1
Quantification of CB1R+ and CCK+ puncta around IT and PT soma.
A) Injection schematic. AAVrg-TdTomato was injected to either the cPFC or the Pag along with AAV-Dlx-Flex-GFP to the PFC in CCK-Cre animals, to label IL IT or PT cells with Td-Tomato and CCK+ axons …
Author response image 2
Quantification of PPR.
Quantification of PPR of CCK+ inputs at IT cells before (black), after (red) and recovery (gray) from depolarization in the DSI experiment (n = 9 cells, 5 animals).
Tables
Key resources table
| Reagent type (species) or resource | Designation | Source or reference | Identifiers | Additional information |
|---|---|---|---|---|
| Strain, strain background (M. musculus, both sexes) | C57BL/6J wild type | Jackson Labs | Stock #: 000664 RRID:IMSR_JAX:000664 | Both sexes |
| Strain, strain background (M. musculus, male) | Pvalbtm1(cre)Arbr (PV-Cre) | Jackson Labs | Stock #: 008069 RRID:IMSR_JAX:008069 | Homozygote male breeder |
| Strain, strain background (M. musculus, male) | Ssttm2.1(cre)Zjh (SOM-Cre) | Jackson Labs | Stock #: 013044 RRID:IMSR_JAX:013044 | Homozygote male breeder |
| Strain, strain background (M. musculus, male) | Ccktm1.1(cre)Zjh (CCK-Cre) | Jackson Labs | Stock #: 012706 RRID:IMSR_JAX:012706 | Homozygote male breeder |
| Strain, strain background (M. musculus, female) | Gt(ROSA)26Sortm14(CAG-tdTomato)Hze (Ai14) | Jackson Labs | Stock #: 007914 RRID:IMSR_JAX:007914 | Homozygote female breeder |
| Other | AAV1-DIO-ChR2-eYFP | UPenn | Cat #: AV-1–20298P | AAV virus expressing Cre-dependent ChR2 |
| Other | AAV1-ChR2-eYFP | UPenn | Cat #: AV-26973P | AAV virus expressing ChR2 |
| Other | AAV1-DIO-eYFP | UPenn | Cat #: AV-1–27056 | AAV virus expressing Cre-dependent eYFP |
| Other | AAVrg-GFP | Addgene | Cat #: 37825-AAVrg RRID:Addgene_37825 | Retrograde virus expressing GFP |
| Other | AAVrg-TdTomato | Addgene | Cat #: 59462-AAVrg RRID:Addgene_59462 | Retrograde virus expressing TdTomato |
| Other | AAV-Dlx-Flex-GFP | Addgene | Cat #: 83900 RRID:Addgene_83900 | AAV virus expressing Cre-dependent GFP in interneurons |
| Other | AAV-Dlx-Flex-ChR2-mCherry | This paper | AAV virus expressing Cre-dependent ChR2 in interneurons | |
| Antibody | Anti-PV (mouse, monoclonal) | Millipore | Cat#: MAB1572 RRID:AB_2174013 | (1:2000) |
| Antibody | Anti-CB1R (guinea pig, polyclonal) | Frontier Institute | Cat#: Af530 RRID:AB_2314113 | (1:500) |
| Antibody | Anti-SOM (rat, monoclonal) | Millipore | Cat#: MAB354 RRID:AB_2255365 | (1:200) |
| Chemical compound, drug | WIN 55,212–2 | Tocris | Cat#: 1038 | 1 µM |
| Chemical compound, drug | AM-251 | Tocris | Cat#: 1117 | 10 µM |
