Hypothalamic aromatase activity in young and old male rats.
Hypothalamic aromatase activity in young and old male rats.
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年轻和年老雄性大鼠的下丘脑芳香酶活性。
DOI：
10.1016/0197-4580(86)90150-8
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发表时间：
1986
影响因子：
4.2
通讯作者：
Resko,JA
中科院分区：
文献类型：
--
作者：
Roselli,CE;Kaler,LW;Resko,JA
我们研究了年轻(3-4个月)和老年(22-24个月)雄性大鼠下丘脑组织将雄激素芳香化为雌激素的能力。用放射测定法测量脑组织匀浆中芳香化酶的活性，该测定法以[1β-~3H]雄烯二酮的立体特异性产生3H2O作为雌激素形成的指标。尽管男性血液中的睾酮(T)水平随着年龄的增长下降了40%，但我们发现下丘脑的芳香酶活性不受年龄的影响。这一发现表明，长期暴露于低水平的循环T可以维持老年雄性大鼠脑芳香酶的活性。在一项旨在检测下丘脑芳香酶活性对T诱导的急性反应的实验中，我们发现两个年龄组的循环T水平与下丘脑芳香酶活性之间存在显著的正相关。这些结果表明，T仍然是老年雄性大鼠下丘脑芳香酶的有效调节剂。
We studied the capability of hypothalamic tissue from young (3–4 months) and old (22–24 months) male rats to aromatize androgens to estrogens. Aromatase activity was measured in homogenates of brain tissue by using a radiometric assay that quantifies the stereospecific production of3H2O from [1β-3H]androstenedione as an index of estrogen formation. Despite the 40% drop in circulating testosterone (T) levels associated with aging in males, we found that hypothalamic aromatase activity was unaffected by age. This finding suggested that chronic exposure to low levels of circulating T can maintain brain aromatase activity in aged male rats. In an experiment designed to examine the acute response of hypothalamic aromatase activity to induction by T, we found a significant positive correlation between circulating T levels and hypothalamic aromatase activity in both age groups. These results demonstrate that T remains an effective regulator of hypothalamic aromatase in old male rats.