第48回日本神経学会総会
＜シンポジウム11-4＞西太平洋地域の筋萎縮性側索硬化症/パーキンソン痴呆複合（ALS/PDC）と関連神経変性疾患
紀伊半島ALS/PDCの原因，とくにミネラル仮説について
吉田 宗平1）, 紀平 為子2）, 八瀬 善郎1）
1）関西医療大学神経病研究センター〔〒590-0482 大阪府泉南郡熊取町若葉2-11-1〕
2）和歌山県立医科大学神経内科
In 1960s, epidemiological surveys in both Kozagawa and Hobara foci revealed the characteristics of Kii ALS as follows; younger age at onset, M/F ratio of 1.5-1.8: 1, familial clustering and presence of Alzheimer's neurofibrillary tangles (NFTs). The segregation ratio of six families in Hobara was estimated 0.304±0.096 ( p±95% confidence level), suggesting a multifactorial inheritance.
Kii environmental studies showed that extremely low contents of calcium (Ca) and magnesium (Mg) in the birthplace's rivers of ALS patients inversely and significanthy correlated with high mortality rates, aluminum (Al) contents, and densities of hipocampal NFTs. In experimental animals, a low Ca and Mg, and high Al content diet led to a neuronal loss with axonal swellings and chromatolysis, and positive staining of cortical neurons with anti-PHF antibodies. Recently, a significant loss of dopaminergic neurons was identified exclusively in the substantia nigra in 1-year-old rat fed under a low Mg intake over two generations.
Kii people may have a predisposition to develop ALS/PDC precipitated by their environmental status, suggesting gene-environmental interactions.
(臨床神経, 47：970−973, 2007)
key words：紀伊半島筋萎縮性側索硬化症/パーキンソン痴呆複合, カルシウム, マグネシウム, アルミニウム, 遺伝子・環境相互作用
（受付日：2007年5月16日）
