Nerve fibres may play an important role in the mechanisms of pain generation in endometriosis

October 2006

Researchers in Australia have identified more nerve fibres in peritoneal endometriotic lesions than in normal peritoneum

Peritoneal endometriotic lesions and normal peritoneum were prepared from women with and without endometriosis (n = 40 and 36, respectively). Specimens were also prepared from endosalpingiosis lesions (n = 9). These sections were stained immunohistochemically with antibodies against protein gene product 9.5, neurofilament (NF), nerve growth factor (NGF), NGF receptor p75 (NGFRp75), substance P (SP), calcitonin gene-related peptide (CGRP), acetylcholine (ACh) and tyrosine hydroxylase (TH) to demonstrate myelinated, unmyelinated, sensory, cholinergic and adrenergic nerve fibres.

The authors identified significantly more nerve fibresin peritoneal endometriotic lesions than in normal peritoneum (P < 0.001) or endosalpingiosis lesions (P < 0.001). These nerve fibres were SP, CGRP, ACh or TH immunoreac-tive. Many of these markers were co-localized. There was an intense NGF immunoreactivity near endometriotic glands, and NGFRp75 immunoreactive nerve fibres were present near endometriotic glands and blood vessels in the peritoneal endometriotic lesions.

The team concluded that peritoneal endometriotic lesions were innervated by sensory Ad, sensory C, cholinergic and adrenergic nerve fibres, and that these nerve fibres may play an important role in the mechanisms of pain generation in endometriosis.

Source

Tokushige N, Markham R, Russell P, Fraser IS. Nerve fibres in peritoneal endometriosis. Hum Reprod 2006;21(11):3001-7