High density of small nerve fibres in the functional layer of the endometrium in women with endometriosis

March 2006

Researchers in Australia suggest that small nerve fibres detected in the functional layer in all women with endometriosis may have important implications for understanding why pain occurs in these patients.

Tokushige et al prepared histological sections of endometrial tissue from endometrial curettings and hysterectomies performed on women with endometriosis (n=25 and n=10, respectively) and without endometriosis ((n=47 andn=35, respectively). These were stained immunohistochemically for the highly specific polyclonal rabbit anti-protein gene product 9.5 (PGP9.5) and monoclonal mouse anti-neurofilament protein (NF) in order to demonstrate both myelinated and unmyelinated nerve fibres.

The team was able to identify small nerve fibres throughout the basal and functional layer of the endometrium in all endometriosis patients, but these were not seen in the functional layer of the endometrium in any of the women without endometriosis (p<0.001).

NF-immunoreactive nerve fibres were present in the basal layer in all endometriosis patients but not in non-endometriosis patients, with on exception (p<0.001).

Tokushige et al summarises: “This demonstration of small nerve fibres in the functinal layer of eutopic endometrium of women with endometriosis is so striking in the present study that we believe it could become a relatively simple surrogate marker of this condition using endometrial biopsies. It is even possible that an endometrial biopsy may demonstrate nerve fibres in women destined to develop the condition later in life”.

They conclude that further research is required to define the possible roles and mechanisms of these nerve fibres in endometriosis and other gynaecological conditions.

Source

Tokushige N, Markham R, Russell R, and Fraser IS. High density of small nerve fibres in the functional layer of the endometrium in women with endometriosis. Human Reprod 2006; 21(3): 782-787.