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■裸鼹鼠全身無毛，皮膚呈粉紅色，通常住在地下道。資料圖片
裸鼹鼠不患癌，不怕酸也不怕老，有些裸鼹鼠的年紀甚至比負責研究的大學人員還要老。
芝加哥伊利諾伊大學生物學教授帕克笑說：「這些真的是火星老鼠。」事實上，裸鼹鼠來自非洲之角，現已越來越受各地研究單位歡迎。裸鼹鼠能活30年，擁有探索人類健康的潛質，所以常用於老化、癌症和中風的研究。
聖安東尼奧的得州大學健康科學中心目前約有1,500隻裸鼹鼠，是研究員比弗斯坦的得意之作。這個鼠群全被養在以長管相連的透明槽中，是全美最大的裸鼹鼠群。此外，美國至少還有6所大學也飼養裸鼹鼠。
裸鼹鼠幾乎全盲，全身無毛，外形有如長了細腿與獠牙的皺皮春卷，通常住在地下道，擁有類似蜜蜂的社會組織。
一般實驗鼠平均壽命兩年，而裸鼹鼠可活到30年。比弗斯坦說，裸鼹鼠骨質要到超過24歲才開始退化。雖然裸鼹鼠看似脆弱(一隻手掌就能放好幾隻，桃紅色皮膚看似透明)，但牠其實是特技硬漢。
普通人的傷口被噴上檸檬汁一定會覺得刺痛，但裸鼹鼠卻不然，因為牠們缺乏一種叫做P物質的神經遞質。這一發現已為疼痛研究開啟新頁。
至於癌症，比弗斯坦說，裸鼹鼠身上一直沒有患上。今年10月發表的一份研究發現，裸鼹鼠的抗癌秘訣可能來自一種名叫p16、能避免細胞結集的基因。癌症出現是因為細胞不受控制地生長。
研究員拉森將於下月出版的《神經報告》期刊中指出，成年裸鼹鼠的大腦可最少忍受缺氧半小時，這發現將有助中風研究。 ■綜合外電消息 羅國偉 資深翻譯員
Naked Mole Rats are Long-lived and Cancer-Resistant
Naked mole rats don't get cancer. They shrug off brushes with acid and age so well, some are older than the college-aged researchers handling them.
"They really are from Mars," said Thomas Park, a professor of biological sciences at the University of Illinois at Chicago.
Actually, they're from the horn of Africa. But naked mole rats are becoming more popular in research laboratories, where the seemingly invulnerable rodents have surprised scientists with their ability to live up to 30 years and their potential to offer insights into human health. They're being used to study everything from aging to cancer to strokes.
About 1,500 naked mole rats live in clear tanks connected by long tubes at the University of Texas Health Science Center in San Antonio, where researcher Rochelle Buffenstein nurtures the largest colony in the U.S. At least a half-dozen other universities also have colonies.
Nearly blind and hairless, the rodents resemble wrinkled spring rolls with tiny legs and buck teeth. They normally live in underground tunnels with a social structure comparable to bees.
Whereas laboratory mice live an average two years, naked mole rats can live up 30 years with little creaking in old age. Buffenstein said their bone quality doesn't start to diminish until they're about 24 years old. They look fragile-several can fit into a palm, and it's possible to see beneath their pinkish skin-but naked mole rats are like tough, tube-shaped stuntmen.
Squirting lemon juice on a cut would sting anyone, but naked mole rats don't feel pain because they lack a neurotransmitter known as substance P. The discovery has opened up ideas for pain research.
Cancer? Buffenstein said the disease has never been found in the rodent.
A study published in October found their resistance may come from a gene called p16 that prevents cells from crowding together. Cancer occurs when cells grow uncontrollably.
Researcher John Larson report in next month's journal NeuroReport that the brains of adult naked mole rats can withstand oxygen deprivation for a half-hour or more, and that knowledge can eventually help in stroke research. ■AFP
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