Kawate R, Talan M I, Engel B T
Laboratory of Behavioral Sciences, National Institute on Aging, NIH, Gerontology Research Center, Baltimore, MD 21224.
J Gerontol. 1993 Sep;48(5):B180-3. doi: 10.1093/geronj/48.5.b180.
Aged, male C57BL/6J mice produce less heat than adults during cold, which may lead to a reduced ability to maintain core temperature, but the underlying mechanisms of the decreased heat production in aged mice are still unclear. We measured sympathetic nervous activity (SNA) to interscapular brown adipose tissue (IBAT) in aged mice and compared this activity with that of adults. Mice were anesthetized by urethane and isoflurane, and SNA was recorded from one of the fine nerves to IBAT. The animal's body caudal to the pelvic area was covered with a plastic bag containing iced-water to decrease colonic temperature 7 degrees C below control over 20 minutes. SNA to IBAT (IBAT-SNA) increased during cold in both groups, but aged mice had higher IBAT-SNA before and during cold. These findings indicate that neither the ability of aged mice to detect cold nor their ability to generate sympathetic outflow to BAT is deficient.
老年雄性C57BL/6J小鼠在寒冷环境中产生的热量比成年小鼠少，这可能导致维持核心体温的能力下降，但老年小鼠产热减少的潜在机制仍不清楚。我们测量了老年小鼠肩胛间棕色脂肪组织（IBAT）的交感神经活动（SNA），并将其与成年小鼠的这种活动进行比较。小鼠用乌拉坦和异氟烷麻醉，从一条通向IBAT的细神经记录SNA。动物盆腔以下的身体用一个装有冰水的塑料袋覆盖，以在20分钟内将结肠温度降低至比对照低7摄氏度。两组小鼠在寒冷期间IBAT的SNA（IBAT-SNA）均增加，但老年小鼠在寒冷前和寒冷期间的IBAT-SNA更高。这些发现表明，老年小鼠检测寒冷的能力及其向棕色脂肪组织产生交感神经输出的能力均无缺陷。
