多数のLewy小体が大脳灰白質中に見出された特発性パーキンソニズムの1例—神経細胞封入体の電子顕微鏡的研究

A CASE OF IDIOPATHIC PARKINSONISM WITH MANY LEWY BODIES IN THE CEREBRAL CORTEX

I．はじめに

　Lewyは1912年に特発性パーキンソニズムの患者の無名域と迷走神経背側運動核の神経細胞に円形の封入体が存在することを報告した^13）。この封入体はその後，Lafora,TeretiakoffによりLewy小体と名付けられた。続いて，この小体の中枢神経系における分布や組織化学的特徴が研究された^1,2,14）。また特発性パーキンソニズム以外の疾患でも，Lewy小体あるいは類似の封入体の出現が報告されたが^{10,11,18,19）}，しかし量的には特発性パーキンソニズムに圧倒的に多く出現することも知られて来た^1,6,14）。Lewy小体の中枢神経系内分布についての現在までの報告では，Lewy小体は種々の脳幹神経核と中枢神経系以外では自律神経節^2,7,22）に限られ，大脳皮質には出現しないと考えられている^21）。今回，われわれは，臨床的に特発性パーキンソニズムの特徴をもち，従来報告されている領域以外に大脳皮質に広汎に神経細胞封入体が存在する一症例を経験したが，本論文では封入体の電子顕微鏡（以下，電顕と略）所見を報告し，それとLewy小体との関係を明らかにしたい。

One case of idiopathic parkinsonism, which showeda specific distribution of Lewy bodies, was examined.In this case, many intracytoplasmic inclusions werefound in the cerebral cortex in addition to theLewy bodies in the brain stem nuclei. Ultramicro-scopically, we compared these inclusions with theLewy bodies in the substantia nigra. Structurally,they had a similarity to the laminated and uniformstructures of Lewy bodies.

As for the laminated intracytoplasmic inclusionsin the cerebral cortex, the central core consisted offibrils of 50 to 100 Angstrom in width and granulesof 50 to 100 Angstrom in diameter. The fibrilsshowed linear profiles and vesicular profiles of 300to 600 Angstrom in diameter. The periphery ofthe core appeared coarser than the central zone.The outer zone was composed of fibrils 50 to 100Angstrom in width and granules of 70 to 150Angstrom in diameter. Several granules formedgroups and showed clustered or moniliform profiles.Their structure was almost similar to that of theLewy bodies in the substantia nigra, but was differ-ent in the following respects : The vesicles in thecore were fewer and coarser, and the fibrils in theouter zone showed no obviously radiary appearance.

The uniform type in the cortex and the substantianigra consisted of fibrils and clustering granules.In addition to these elements many degeneratingcell organelles were scattered there. In the cortex,many intermediate types were observed, too.

Histochemically, the inclusions in the cortexshowed the same staining properties as Lewy bodies.

According to the above mentioned findings weconsidered these inclusions to be immature Lewybodies.