AGE-RELATED-CHANGES IN THE CONCENTRATIONS OF CYTOSOL RECEPTORS FOR SEX STEROID-HORMONES IN THE HYPOTHALAMUS AND PITUITARY-GLAND OF THE RAT
AGE-RELATED-CHANGES IN THE CONCENTRATIONS OF CYTOSOL RECEPTORS FOR SEX STEROID-HORMONES IN THE HYPOTHALAMUS AND PITUITARY-GLAND OF THE RAT
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DOI：
10.1016/0006-8993(81)90596-5
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发表时间：
1981-01-01
期刊：
影响因子：
2.9
通讯作者：
IBAYASHI, H
中科院分区：
文献类型：
--
作者：
HAJI, M;KATO, KI;IBAYASHI, H
在3个生命阶段（雌性90-650日龄，雄性90- 550日龄）的大鼠下丘脑、垂体和子宫或前列腺的细胞溶胶中测定雌激素和雄激素受体。胞质溶胶17 β的饱和度分析雌性雌二醇受体在300-330天的生命中已经表现出下丘脑和子宫中最大结合能力的显著年龄相关性降低，但脑垂体中没有显著变化。细胞质17 β-雌二醇的结合亲和力、类固醇特异性、沉降系数、化学性质和热不稳定性没有差异。3个年龄组中这些组织的雌二醇结合。在男性中，17 β-受体的每一种雌二醇、睾酮和5.通过蔗糖密度梯度离心从下丘脑、垂体和前列腺胞质溶胶中分离双氢睾酮。这些受体在所有年龄组中显示出相同的沉降系数8- 9 S。在出生后300-330天，雄激素与胞质溶胶的结合率已经下降，但在出生后500-550天，雌激素与胞质溶胶的结合率低于年轻成人。性腺切除术后血清促黄体激素水平的增加显着抑制与年龄的女性和男性。显然，与年龄相关的细胞质性类固醇激素受体的减少归因于结合位点数量的变化。这些增龄性变化可能与老年大鼠下丘脑-垂体-性腺轴反馈系统功能障碍有关。
Estrogen and androgen receptors were measured in cytosols from hypothalamus, pituitary and uterus or prostate of rats at 3 stages in life, from 90-650 days old in females and from 90-550 days old in males. Saturation analysis of cytosol 17.beta.-estradiol receptors in females demonstrated a significant age-associated reduction in maximum binding capacity in hypothalamus and uterus already at 300-330 days of life, but there was no significant change in pituitary gland. There was no difference in binding affinity, steroid specificity, sedimentation coefficient, chemical nature and heat lability of cytosol 17.beta.-estradiol binding of these tissues among the 3 age groups. In males, each receptor for 17.beta.-estradiol, testosterone and 5.alpha.-dihydrotestosterone was isolated by sucrose density gradient centrifugation from hypothalamic, pituitary and prostate cytosols. These receptors showed the same sedimentation coefficient of 8-9S in all age groups. Androgen binding by cytosols already decreased at 300-330 days of life, but estrogen binding was lower at 500-550 days of life than in younger adults. The increase in the serum lutropin level after gonadectomy was significantly depressed with aging in both females and males. Apparently the age-associated reduction in cytosol sex steroid hormone receptors was ascribable to changes of numbers of binding sites. These age-related changes may be concerned with feedback system dysfunction of hypothalamic-pituitary-gonadal axis in aged rats.