On the morphology of the mesencephalic trigeminal cells. New data based on tracer studies.
Injections of free horseradish peroxidase in the masticatory muscles of the cat resulted in retrograde labeling of not only large and small so-called pseudounipolar cells but also of multipolar neurons within the ipsilateral mesencephalic trigeminal nucleus. The latter cell type was present only in the pontine part of the nucleus, and usually more faintly labeled than the other cells. Several of the so-called pseudounipolar cells showed cell processes similar to dendrites of other cells, a finding indicating that the afferent connections of these cells are much more complex than hitherto assumed. The observations are discussed also with reference to the problem whether the multipolar cells should be considered as displaced locus coeruleus neurons.
D000818:Animals; D002415:Cats; D008636:Mesencephalon / Q000166:cytology; D009474:Neurons / Q000166:cytology; D014278:Trigeminal Nuclei / Q000166:cytology*