The effects of pelvic neurectomy on collagen in the cervix of the pseudopregnant rat

Bilateral section of the pelvic parasympathetic nerves (pelvic-neurectomy) on day 5 of pseudopregnancy had no effect on the wet weight of ovaries, uteri, and/or cervices, but at day 9 serum progesterone was reduced to approximately half that of sham-operated animals. Collagen in the cervix was visualized with picrosirius red staining under polarization microscopy. Pelvic neurectomy decreased the birefringence of Type 1 collagen in the cervix to less than half that of sham operated animals. The decreased birefringence, an index of the organization of collagen fibers, is believed to be attributable to reduced progesterone levels. Alternatively, the pelvic nerve may directly influence mucopolysaccharides or collagenolytic enzymes in the cervix.