Peng M T, Kang M
Physiol Behav. 1984 Oct;33(4):615-20. doi: 10.1016/0031-9384(84)90380-9.
Running-wheel activity of 7 young adult male rats (3 to 6.5 months of age) and 11 old male rats (22 to 34 months of age), feeding behavior of 10 each of young adult and old male rats and drinking behavior of 6 each of young adult and old male rats were recorded. Circadian rhythms were lost in 2, 6 and 1 old rats respectively in running activity, feeding and drinking behaviors. Loss of circadian rhythm of three behaviors seems not to occur concomitantly. Although the remaining old rats still showed as high a percentage of nocturnal activities in these three behaviors as young rats, the patterns of the behaviors revealed age-related changes. Old rats had decreased daily activity with small numbers and short duration of bursts of activity. Total frequencies of the head of rats interrupting the photobeam of a feeder during 24 hour period increased in old age with patterns of a small number of long meals with a rapid ingestion rate. Total numbers of licking the spout per day increased in old rats with patterns of a small number of short duration draft with a rapid licking rate. Old rats still maintained diurnal difference of drinking-to-feeding ratio. The similarity of the feeding and drinking patterns between old male rats and ventromedial hypothalamus lesioned rats was discussed.
记录了7只年轻成年雄性大鼠（3至6.5个月龄）和11只老年雄性大鼠（22至34个月龄）的转轮活动、10只年轻成年和10只老年雄性大鼠的进食行为以及6只年轻成年和6只老年雄性大鼠的饮水行为。在跑步活动、进食和饮水行为中，分别有2只、6只和1只老年大鼠的昼夜节律丧失。三种行为的昼夜节律丧失似乎并非同时发生。尽管其余老年大鼠在这三种行为中的夜间活动百分比仍与年轻大鼠一样高，但行为模式显示出与年龄相关的变化。老年大鼠的日常活动减少，活动爆发的次数少且持续时间短。在24小时内，老年大鼠头部打断喂食器光束的总频率增加，进食模式为少量多餐且进食速度快。老年大鼠每天舔舐饮水口的总次数增加，饮水模式为少量短时间饮水且舔舐速度快。老年大鼠仍保持着饮水与进食比例的昼夜差异。讨论了老年雄性大鼠与腹内侧下丘脑损伤大鼠在进食和饮水模式上的相似性。
