第23回日本神経科学大会・第10回日本神経回路学会合同大会
2000.9.4-9.6 (横浜)

サル下側頭葉皮質TEや前腹側部と嗅周皮質における内在性水平軸索
王 全新1、川嵜圭祐1、藤田一郎1,2

1科学技術振興事業団CREST, 2大阪大学 基礎工 認知脳科学

サルのV1からV2、V4、TEOを経てTedに至る腹側視覚系路は視覚記憶に関与するTE野前腹側部(Teav)さらに嗅周皮質(36,35野)へ情報を伝える。腹側経路各領野では、錐体細胞の水平軸索枝が各の領野内で終末集塊(パッチ)を形成している。今回、我々はTEavと36野における水平軸索の形態を検討するために、両領域に順行性軸索トレーサー(BDA)を注入した。どの注入例でも、水平軸索は明瞭なパッチを形成し、注入部位を中心に前後約7mm分布した。TEav注入例では、水平軸索パッチはTEavのみならず36野にも現れ、35野には白質を経由した投射が見られた。36野注入例では、水平軸索パッチは36野、35野、TEavに見られた。この結果は、TEavや多感覚性連合野である36野も視覚性新皮質と同様に水平軸索パッチを有し、これらの領域に機能的単位構造が存在する可能性を示唆するとともに、これら隣接領域が水平軸索により統合していることを示す。

P-108 Patterns ot Intrinsic and Extrinsic Connections in TEav and Perirhinal Cortex in Macaque Monkey

Neurosci. Res. Suppl. 24: S72

Quanxin Wang 1, Keisuke Kawasaki 1. Ichiro Fujita 1,2
1CREST, Japan Science and Technology Corporation, Japan, 2Graduate School of Engineering Science, Osaka Univ. Toyonaka. Japan

The anteroventral part of the inferior temporalcortex (TEav) and the perirhinal cortex (PRh) are critically involved in visual recognition memory. To advance our understanding of the functions carried out by these regions, it is essential to know the patterns of their intrinsic and extrinsic neural connections. In the present study, we investigated the projection pattens of intrinsic horizontal axons within each area as well as the pattern of exrinsic, area-to-area, projections of these areas by making small extracellular injections of an anterograde axon tracer, biotinylated dextran amine. The results indicate that horizontal axons both in TEav and area 36 produce patches of terminals similar to those in the immediately earlier area, TEad. Area 36 and TEav are reciprocally connected both by axons running in layers 2 and 3 and by axons passing through the white matter. The organization of extrinsic connections was different between TEav and area 36. Injections in TEav led to extrinsic label in the upper and lower bank of STS, areas 35 and 36, TEpV and TF. An injection near the TEav/36 border led to extrinsic label in the lower bank of STS, area 35 and 36. TEpv and TF. Injections in area 36 led to extrinsic label in TEav, area 36 and the entorhinal cortex. The results indicate that 1) these multimodal, memory-related areas also have modular patches of horizontal axons, and 2) the two areas, which are functionally closely related to each other, have different projections areas.


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