(A,A′) HSV129ΔTK-TT.
(B–D) tdT (red) in HSV129ΔTK-TT-injected
Crfr2α-eGFPCre mice counterstained with DAPI (blue)
at 1 (B) or 3 (C,D) days post-injection (dpi) in LS (B,C) or medial hypothalamus
(D). Dashed lines in (D) demarcate PVN (upper right) and AHA (lower left).
(E–G) Combined CRACM and retrograde tracing. (F) A slice used for
recording;
Crfr2α+ChR2-YFP+
axons originating from LS (green), retrobeads (red), and two neurobiotin-filled
neurons (blue). The cell that yielded the traces in (G) is shown at higher
magnification in the inset. (G) A 2ms pulse of 473nm light induced monosynaptic
IPSCs in 4/9 retrobead+ AHA neurons that were sufficient to
inhibit firing (G′).
(H,I) Optogenetic stimulation of LS
Crfr2α+ neurons increased CORT.
eYFP(n=9) vs. ChR2(n=9):
CORT, ng/ml (159.2±9.3 vs. 228.8±30.9,
P<0.05).
(J,K) Optogenetic inhibition of LS
Crfr2α+ projections to AHA
decreased CORT. hrGFP(n=15) vs.
ArchT-GFP(n=17): CORT, ng/ml (162.1±8.6 vs.
134.5±4.1, P<0.01).
Values indicate mean±s.e.m.
(L) Proposed model for LS Crfr2α+
neuronal control of stress-induced anxiety.
See also Figure S7.