Journal: Nature Communications
Article Title: Prostaglandin E2 mediates sensory nerve regulation of bone homeostasis
Figure Lengend Snippet: Deletion of PGE2 receptor EP4 in sensory nerve results in bone loss. a Double-immunofluorescence images of femoral bone sections from 12-week-old EP4 wt or EP4 Avil −/− mice using antibodies against EP4 (red) and CGRP (green). DAPI stains nuclei blue. Scale bar, 50 μm. b , c Representative μCT images of femurs from 12-week-old EP4 wt and EP4 Avil −/− mice. Quantitative analysis of trabecular bone fraction (Tb. BV/TV), trabecular number (Tb. N), cortical thickness (Ct. Th), and cortical bone volume (Cor. BV). d ELISA analysis of serum PGE2 level in 12-week-old EP4 wt and EP4 Avil −/− mice. e Representative images of immunostaining and quantitative analysis of the COX2 + cells (in brown) on trabecular bone surface of femoral bone from 12-week-old EP4 wt and EP4 Avil −/− mice. Scale bar, 20 μm. f Histomorphological analysis of osteoblast (N.Ob/B.Pm) and osteoclast (N.Oc/B.Pm) numbers on the trabecular bone surface of femurs of 12-week-old EP4 wt and EP4 Avil −/− mice. g ELISA analysis of serum OCN and CTX levels in 12-week-old EP4 wt and EP4 Avil −/− mice. h Representative trichrome staining and quantitative analysis of osteoid surface per bone surface (OS/BS) in femoral bone tissue of 12-week-old EP4 wt and EP4 Avil −/− mice. Scale bar, 50 μm. i , j Ten-week-old EP4 wt and EP4 Avil −/− mice were injected with vehicle or 3 mg per kg per day PGE2 for 3 consecutive days, and bone samples were harvested 12 days after injection. Calcein was injected 5 days and 1 day before sacrifice. Representative images of calcein double labeling of femoral trabecular bone with quantification of mineral apposition rate (MAR) and bone formation rate (BFR). Scale bar, 20 μm. N ≥ 5 per group. * P
Article Snippet: Briefly, we injected 0.1% calcein (Sigma-Aldrich, C0875) in phosphate-buffered saline at a concentration of 10mg per kg into the mice subcutaneously 7 days and 1 day before sacrifice.
Techniques: Immunofluorescence, Mouse Assay, Enzyme-linked Immunosorbent Assay, Immunostaining, Staining, Injection, Labeling