Identification of sympathetic preganglionic neurons controlling the small intestine in hamsters using a recombinant...

Sympathetic preganglionic neurons (SPNs) may be organized topographically within the spinal cord for selective control of visceral organs. We used a recombinant herpes simplex virus type-1 (rHSV-1) to identify SPNs innervating the small intestine in hamsters. These SPNs were distributed bilaterally in the cord from the fifth thoracic spinal segment to the second lumbar segment, but predominantly in thoracic segments 5-10. They had morphology similar to that of renal and adrenal SPNs infected with HSV-1. The majority of intestinal SPNs were found in the intermediolateral cell column, with a few located in the lateral funiculus. The SPNs labelled following duodenal injection of rHSV-1 were in the same spinal segments as the SPNs labelled following jejunal or ileal injections, suggesting lack of a relation between target topography and the topographic organization of these neurons. In addition, intestinal SPNs were located in the same spinal segments, and autonomic nuclei as renal and adrenal SPNs suggesting that SPNs controlling the abdominal viscera are not organized viscerotopically for discrete control of different organs.