Mast cells may contribute to the development of pain and hyperalgesia in endometriosis

October 2006

The presence of increased activated and degranulating mast cells in deeply infiltrating endometriosis, which are the most painful lesions, and the close histological relationship between mast cells and nerves strongly suggest that mast cells could contribute to the development of pain and hyperalgesia in endometriosis, possibly by a direct effect on nerve structures.

Researchers set out to detect and quantify mast cells in peritoneal, ovarian, and deep infiltrating endometriosis and to study the relationship between mast cells and nerves in endometriosis.

Excision of endometriosis from different anatomical locations was undertaken in 69 women, who were undergoing laparoscopic excision of endometriosis for pain. Thirty-seven biopsies of normal tissue were obtained from women without endometriosis.

The women with deeply infiltrating lesions had significantly higher preoperative pain scores than women with peritoneal or ovarian endometriosis. Mast cells and degranulating mast cells are significantly more abundant in endometriotic lesions than in non-affected tissues. Deep infiltrating lesions show a significantly higher number of mast cells, activated mast cells, and mast cells located <25 mum from nerves than peritoneal and ovarian lesions. The authors found significantly more degranulating mast cells in deep infiltrating lesions than in peritoneal lesions.

Source

Anaf V, Chapron C, El Nakadi I, De Moor V, Simonart T, Noel JC. Pain, mast cells, and nerves in peritoneal, ovarian, and deep infiltrating endometriosis. Fertil Steril 2006;86(5):1336-43