ヒト脳の脚橋被蓋核におけるLafora小体様封入体について

LAFORA-LIKE NEURONAL INCLUSIONS IN THE NUCLEUS TEGMENTALIS PEDUNCULOPONTINUS : THEIR RELATION TO AGING

I．はじめに

　われわれは，ルーチンの剖検例の神経病理学的検索を通じて，中脳被蓋域にしばしばLafora小体にきわめて類似した神経細胞内封入体を有する神経核（脚橋被蓋核；Nucleus tegmentalis pedunculopontinus）が存荘することに気付いた。　Lafora小体は通常Lafora病に大量に出現する封入体として知られているほかには，ごくまれに種々のおもに変性疾患の際に合併して出現することが散発的に報告されているが^{5,7,9,10,13,18,19）}，通常例での出現は，われわれの知る限りでは記載されていない。一方，ヒト以外の動物では，最近Suzukiら^14）によるミオクローヌスてんかんを伴わない通常犬の研究で，Lafora小体様封入体が恒常的かつ老化過程に伴つてその出現頻度を増す封入体であることが明らかにされている。われわれは，ヒト中脳脚橋被蓋核神経細胞内封入体の性質，その出現の意味を知るために，症例の検討と若干の組織化学的検索を行つた結果を報告する。

At routine postmortem examinations, peculiar basophilic inclusion bodies were often encountered in nerve cells of the nucleus tegmentalis pendunculo-pontinus in the lower midbrain. Morphology and histochemistry of these inclusions were most similar to Lafora bodies commonly seen in Lafora type myoclonus epilepsy. Incidence and distribution of such Lafora-like bodies were examined in transverse sections through the lower midbrain of 38 patients selected at random who did not have storage or de-generative diseases. In neurons of 14 out of these 38 cases, at least one Lafora-like body was found. Their distribution was restricted to the nucleus tegmentalis pedunculopontinus. Almost every body occupied the neuronal perikarya to various degrees or they were also seen in the neuropil. Clinical data and autopsy findings revealed age-dependence of these bodies and also probable correlation to cer-ebral infarction : 5 of the 14 positive cases had old cerebral infarcts. In addition to Lafora type myoclonus epilepsy and rare instance of certain degenerative diseases, also aging may induce forma-tion of Lafora-like bodies, though regionally restric-ted, in neurons.