Fallopian tube

The fallopian tube is histologically composed of three layers: a mucosal membrane, a wall of smooth muscle and a serosal coat. The serosa is lined by flattened mesothelial cells. The muscularis mucosae is composed of two layers: an outer longitudinal and an inner circular layer. The mucosa rests directly on the muscularis. It consists of a luminal epithelial lining and a underlying lamina propria with sparse spindle and angulated cells.

Three cell types comprise the epithelial layer: ciliated (20-30%), secretory (55-60%) and intercalary cells. Ciliated cells are believed to be more frequent in the ovarian end of the fallopian tube. The ciliated cell has a columnar shape and contains a oval or round nucleus, often located perpendicular or parallel to the long axis of the cell. The secretory cell is usually a more narrow columnar cell with approximately the same height as the ciliated cell. The nucleus is ovoid and perpendicular to the long axis of the cell. The chromatin is more dense and the nucleolus smaller than that seen in the ciliated cell. The intercalary cell, or peg cell is a columnar cell occupied chiefly by a thin, dark-staining nucleus.