LOCALIZATION OF VASOACTIVE INTESTINAL PEPTIDE IMMUNOREACTIVITY IN HUMAN-FETUS AND NEWBORN-INFANT SPINAL-CORD

Using an indirect immunofluorescence method the distribution of vasoactive intestinal peptide (VIP) immunoreactivity was studied in human fetus and newborn infant spinal cord and dorsal root ganglia. For comparison some newborn infant brains were investigated. VIP-like immunoreactive fiber were exclusively found in the caudal spinal cord and corresponding dorsal root ganglia. No immunoreactive cell bodies were detected. The first appearance of VIP-like immunoreactive fibers in both spinal cord and dorsal root ganglia was suggested during the 4th month of fetal life. Most immunolabeled fibers concentrated in the sacral segment were distributed in the Lissauer tract, along the dorsolateral gray border, in the intermediolateral areas and near the central canal in the dorsolateral commissure. A few VIP-like immunoreactive fibers were seen in the dorsal funiculus and occasionally in the ventral gray horn and ventral roots. A large population of VIP-like immunoreactive fibers occurs longitudinally in dorsal root, in ganglia and in the spinal nerve exit zone. Evidently, VIP-like immunoreactive fibers appear early in the human fetus spinal cord and corresponding ganglia. In both fetus and newborn infant spinal cord VIP-like immunoreactive fiber distribution is limited to the lumbosacral segment.