THE ORIGINS OF THE DESCENDING PRO-PRIOSPINAL TRACT AND THE CONNEC-TIONS OF THE NUCLEUS DORSOLA-TERAL FUNICULUS IN THE SPINAL CORD OF THE RAT / 解剖学报

HRP solution was injected into the right side of the thoracic spinal cord of the rat with a micropipette to observe the neurons which give rise to the descending propiospinal tract. Labeled neurons were distributed throughout the bilateral Rexed's laminae Ⅰ-Ⅹ of the spinal cord in the segments rostral to the site of HRP application. The greatest number of the labeled cells were consistently found in lamina Ⅶ (including the intermediolateral nucleus), and then in laminae Ⅷ and Ⅳ. Our results verified the existence of the nucleus of the dorsolateral funiculus and its intraspinal connections in the spinal cord of the rat. This nucleus gives rise to the descending projections to the lower spinal segments.