Figure 1

Staining for estrogen receptors of LF cells. (A) and (C) showed ligamentum flavum cells taken from a female patient. (B) and (D) showed ligamentum flavum cells taken from a male patient. In (A) and (B), cells were stained for estrogen receptor β. In (C) and (D), cells were stained for estrogen receptor α. Positively stained cell are brown in color (arrow). Some cells in (C) and most of the cells in (D) were not stained by antibodies showing blue in color (arrow heads).