Two types of neuron are found within the PPT, a small percentage of which project to both the LM-SG and SC.
The pedunculopontine tegmental nucleus (PPT) projects its cholinergic fibers to both the lateralis medialis-suprageniculate nucleus (LM-Sg) and the superior colliculus (SC). For the purpose of verification of whether a single neuron in the PPT projects to both the LM-Sg and the SC, we injected dextran tetramethylrhodamine (DR) into the LM-Sg and dextran fluorescein (DF) into the ipsilateral SC. The DR-positive neurons labeled retrogradely in the PPT are small (mean: 27.13+/-1.22 micro m) and distributed in the rostral two-thirds of this nucleus, whereas the DF-positive neurons are small (mean: 27.54+/-1.16 micro m) or medium-sized (mean: 40.18+/-1.43 micro m), and are located throughout the PPT. Thirty-five percent of all labeled neurons are double-labeled and small. The present study indicates that the PPT projection to the LM-Sg in part involves neurons bifurcating to the SC.
Hoshino
Kaeko
K
Division of Neurobiology and Anatomy, Department of Sensory and Integrative Medicine, Niigata University Graduate School of Medical and Dental Sciences, Asahimachi, 951-8510 Niigata, Japan. hoshinok@med.niigata-u.ac.jp
Nagy
Attila
A
Eördegh
Gabriella
G
Benedek
György
G
Norita
Masao
M
D000109:Acetylcholine / Q000378:metabolism; D000818:Animals; D001369:Axons / Q000502:physiology / Q000648:ultrastructure; D002415:Cats; D048429:Cell Size / Q000502:physiology; D002799:Cholinergic Fibers / Q000378:metabolism / Q000648:ultrastructure; D003911:Dextrans; D016650:Fluorescein-5-isothiocyanate / Q000031:analogs & derivatives*; D009434:Neural Pathways / Q000033:anatomy & histology* / Q000502:physiology; D009474:Neurons / Q000145:classification / Q000166:cytology* / Q000502:physiology; D045042:Pedunculopontine Tegmental Nucleus / Q000033:anatomy & histology* / Q000502:physiology; D020656:Posterior Thalamic Nuclei / Q000033:anatomy & histology* / Q000502:physiology; D011597:Psychomotor Performance / Q000502:physiology; D012235:Rhodamines; D013477:Superior Colliculi / Q000033:anatomy & histology* / Q000502:physiology; D014795:Visual Pathways / Q000033:anatomy & histology / Q000502:physiology
D003911:Dextrans; C067661:Fluoro-Ruby; D012235:Rhodamines; C015219:fluorescein isothiocyanate dextran; D016650:Fluorescein-5-isothiocyanate; D000109:Acetylcholine