Distribution of cells of origin of the corticotrigeminal projections to the nucleus caudalis of the spinal trigeminal complex in the cat. A horseradish peroxidase (HRP) study.

The cortical distribution of cells of origin of the corticotrigeminal projections to the nucleus caudalis of the cat was examined using the method of retrograde axonal transport of horseradish peroxidase (HRP). After injections of HRP into the nucleus caudalis, labeled cells were distributed densely in the anterior suprasylvian gyrus, the coronal gyrus, and the ventral part of the anterior sigmoid gyrus, and moderately in the rostral part of the anterior ectosylvian gyrus on the contralateral side. In the anterior suprasylvian gyrus, the distribution extended rostrocaudally from the lateral ansate sulcal level to about 4.0 mm caudal to this level and mediolaterally throughout the convex of the anterior suprasylvian gyrus. All cortical labeled cells were pyramidal cells of various sizes in layer V.