• 作者： 蔡元奮; 戴美雪; 王慧如; 盧國賢
• 作者服務機構： 國立臺灣大學醫學院生理學科及解剖學科
• 中文摘要： 本研究旨在探討年齡與長期節食對恆溫動物體溫的影響。以年齡為3.5個月（年輕組）及14.5個月（中年組）的Long-Evans 雄性大花鼠－－共計 48 隻，作為實驗材料。每隻大花鼠皆單獨置放於動物籠內，以 Purina 動物飼料飼餵。根據飼餵處理方式的不同，同年齡的實驗動物，再區分為如下兩組：任意進食（ad libitum-fed）組和節食（dict-restricted）組。前者的飼量和飲水量皆不予限制，而後者僅給予同年齡任意進食組飼量的一半，但飲水量則不予限制，此飼量的控制持續8週。在節食實驗進行期間，每週測量動物的體溫及體重一次。節食8週之後，每隔 3小時進行一次動物體溫的測量，以觀察各組動物體溫在 24 小時內的變化。 實驗的結果如下：（l）自節食第5週後開始，中年節食組的體溫，即較中年任意進食組者為低（節食第5、6週後P＜0.05，節食第7、8週後p＜0.01），亦較年輕節食組者明顯降低（節食第5週至第8週P＜0.01）。（2）節食8週之後，各組動物體溫24小時的週期變化型（circadian Pattern）甚為相似，但中年節食組其體溫24小時週期變化幅度的峰谷值差距（peak-trough difference）雖較年輕節食組者為小（P＜0.05），但與中年進食組者比較，並無差別。（3）節食8週後，中年節食組的平均體溫較中年任意進食組者為低（p＜0.001），也較年輕節食組者為低〈p＜0.001）。（4）比較任意進食處理的年輕及中年兩組大花鼠的平均體溫，二者間沒有顯著的差異。 本研究的結果顯示，「年齡」對任意進食動物的平均體溫及其24小時週期的變化至少在鼠齡為14.5個月之前，並無影響。然而，「節食」對體溫的影響因動物「年齡」的不同而有所差異。
• 英文摘要： Effects of long-term dietary restriction on body temperature and its circadian changes were investi-gated in 3.5- and 14.5-month-old male Long-Evans rats. Animals were either fed ad libitum or kept on arestricted diet for 8 weeks. Purina Lab Chow was constantly available to the ad libitum-fed groups,whilehalf portions of their daily food consumption were given to age-matched diet-restricted groups every day.A highly significant lowering of body temperature in middle-aged diet-restricted (MR) rats was not observeduntil their food intake had been restricted for 5 weeks compared with that of the middle-aged ad libitum-fed (MA) group as well as that of the young diet-restricted (YR) rats. Eight weeks after diet restriction,both the circadian pattern of body temperature and its diurnal peak-trough difference remained almostunchanged in all four groups, while the average body temperature of MR rats was greatly lower than thatof the YR group and that of MA animals. No significant difference in average body temperature was foundbetween the young ad libitum-fed (YA) rats and the MA group. These data suggest that the average bodytemperature and its circadian changes in ad libitum-fed rats，at least before the age of 14.5 months, is notage-related, while the effect of dietary restriction on body temperature may be modified with increasingage.
• 中文關鍵字： aging; dietary restriction; body temperature; circadian rhythm
• 英文關鍵字： --