Mooradian A D, Li J, Shah G N
Division of Endocrinology, Diabetes and Metabolism, Department of Internal Medicine, St. Louis University Medical School, St. Louis, MO 63104, USA.
Brain Res. 1998 May 18;793(1-2):302-4. doi: 10.1016/s0006-8993(98)00144-9.
To determine if aging in rats is associated with insensitivity of cerebral tissue to thyroid hormones (TH), the expression of a TH responsive protein or (THRP) in cerebral tissue was studied in male Fischer rats at 4, 12 and 24 months of age during euthyroid, hypothyroid and hyperthyroid states. The basal levels of THRP mRNA was significantly increased in 24-month-old and in 12-month-old rats while THRP mass measured by Western blots was decreased compared to 4-month-old rats. Compared to euthyroid rats, hyperthyroidism in 4-month-old rats was associated with 5.1-fold increase in THRP mRNA and 3.7-fold increase in protein content while in hyperthyroid aged rats, the increase of THRP mRNA was only 1.6-fold and the increase in the protein was 2.4-fold. Hypothyroidism did not significantly alter THRP or its mRNA in either young or aged rats. It is concluded that aging in rats is associated with reduced cerebral tissue responsiveness to thyroid hormones.
为了确定大鼠衰老是否与脑组织对甲状腺激素（TH）不敏感相关，我们在正常甲状腺状态、甲状腺功能减退和甲状腺功能亢进状态下，研究了4、12和24月龄雄性Fischer大鼠脑组织中甲状腺激素反应蛋白（THRP）的表达。与4月龄大鼠相比，24月龄和12月龄大鼠THRP mRNA的基础水平显著升高，而通过蛋白质印迹法测得的THRP质量则降低。与正常甲状腺大鼠相比，4月龄大鼠甲状腺功能亢进时THRP mRNA增加5.1倍，蛋白质含量增加3.7倍，而在老年甲状腺功能亢进大鼠中，THRP mRNA仅增加1.6倍，蛋白质增加2.4倍。甲状腺功能减退在年轻或老年大鼠中均未显著改变THRP或其mRNA。结论是，大鼠衰老与脑组织对甲状腺激素的反应性降低有关。
