Quantitative histological study of spinal afferent innervation on the ventral surface of the cat stomach by horseradish peroxidase (HRP) method.

Retrograde axonal transport of horseradish peroxidase (HRP) was applied to the ventral surface of the cat stomach. We investigated the number, size and distribution of HRP-positive cells in spinal ganglia. The unexpected finding was the wide distribution of these cells from T3 down to L3. This would result in a diffuse pattern of referred pain.