The visual pulvinar in tree shrews I. Multiple subdivisions revealed through acetylcholinesterase and Cat-301 chemoarchitecture.
Tree shrews are highly visual mammals closely related to primates. They have a large visual pulvinar complex, but its organization and relation to visual cortex is only partly known. We processed brain sections through the pulvinar with seven different procedures in an effort to reveal histologically distinct compartments. The results revealed three major subdivisions. A dorsal subdivision, Pd, stains darkly for acetylcholinesterase (AChE) and occupies the dorsoposterior one-third of the pulvinar complex. A ventral subdivision, Pv, stains darkly when processed with the Cat-301 antibody and occupies the ventroanterior fifth of the pulvinar complex along the brachium of the superior colliculus. Unexpectedly, part of Pv is ventral to the brachium. A large central subdivision, Pc, stains moderately dark for AChE and cytochrome oxidase (CO), and very light for Cat-301. Pc includes about half of the pulvinar complex, with parts on both sides of the brachium of the superior colliculus. These architectonic results demonstrate that the pulvinar complex of tree shrews is larger and has more subdivisions than previously described. The complex resembles the pulvinar of primates by having a portion ventral to the brachium and by having histochemically distinct nuclei; the number of nuclei is less than in primates, however.
Lyon
David C
DC
Department of Psychology, Vanderbilt University, 301 Wilson Hall, Nashville, Tennessee 37203, USA.
Jain
Neeraj
N
Kaas
Jon H
JH
D000110:Acetylcholinesterase / Q000378:metabolism*; D000818:Animals; D064026:Calbindins; D011508:Chondroitin Sulfate Proteoglycans / Q000378:metabolism*; D003576:Electron Transport Complex IV / Q000378:metabolism; D010320:Parvalbumins / Q000378:metabolism; D020649:Pulvinar / Q000201:enzymology*; D064030:S100 Calcium Binding Protein G / Q000378:metabolism; D014418:Tupaiidae / Q000033:anatomy & histology; D014793:Visual Cortex / Q000201:enzymology*
D064026:Calbindins; D011508:Chondroitin Sulfate Proteoglycans; D010320:Parvalbumins; D064030:S100 Calcium Binding Protein G; D003576:Electron Transport Complex IV; D000110:Acetylcholinesterase