Estrogen deficiency promotes blood vessels and nerve endings innervation into LFJ. (A) PECAM-1-positive blood vessels (white arrow head) and neurofilament-positive nerve endings (white arrow) in LFJs from different groups. (B and C) Quantitative evaluation of PECAM-1-positive areas and neurofilament-positive areas in LFJ (magnification 600×). Key: **P < 0.05, (N.S.) not significant.