Evidence for thalamic projections from external cuneate nucleus, cell groups Z and X, and the mesencephalic nucleus of the trigeminal nerve in squirrel monkey.
Horseradish peroxidase (HRP) was injected into the thalamic ventral tier of squirrel monkey and the brainstem was examined for the presence of HRP-reactive cells in the external cuneate nucleus (ECN), nuclei Z and X, and the mesencephalic nucleus of the trigeminal nerve (MNV). Results indicate that the ECN, Z and X have a direct projection to contralateral ventral tier. Thalamic projecting cells in the ECN are located predominantly in the medial part of this nucleus. The MNV projects bilaterally to the ventral tier but predominantly to the ipsilateral side. Consequently, the present report establishes evidence that the above nuclei, which are known to be extensively interconnected with cerebellum, spinal cord and/or other brainstem nuclei, also have a thalamic projection in a New World primate, (Saimiri sciureus).
D000818:Animals; D001931:Brain Mapping; D001933:Brain Stem / Q000166:cytology / Q000502:physiology*; D006735:Horseradish Peroxidase; D009474:Neurons / Q000145:classification*; D012453:Saimiri; D009435:Synaptic Transmission; D013788:Thalamus / Q000502:physiology*; D014276:Trigeminal Nerve / Q000502:physiology*
D006735:Horseradish Peroxidase