Demonstration of paracervical ganglion origin for the vasoactive intestinal peptide-containing nerves of the rat uterus using retrograde tracing techniques combined with immunocytochemistry and denervation procedures.

The origin of the abundant vasoactive intestinal peptide (VIP)-immunoreactive nerves in the uterus has not been fully determined. In this study, a fluorescent dye, True Blue was injected into the uterus of rat and 6 days later, neuronal cell bodies of the paracervical ganglion were found to be labelled by this dye. Some of these labelled ganglion cells were also found to contain VIP immunoreactivity by immunocytochemistry. When the preganglionic pelvic and/or hypogastric nerves of rats were sectioned, the VIP-immunoreactive nerves in the uteri were not depleted, indicating that these nerves did not originate from the splanchnic ganglion, dorsal root ganglion or the spinal cord. Therefore it is concluded that VIP-immunoreactive nerves in the uterus originate from the paracervical ganglion.