White J O, Thrower S, Lim L
Biochem J. 1978 Apr 15;172(1):37-47. doi: 10.1042/bj1720037.
Simultaneous measurements were made of the specific oestrogen receptor in the nuclear and cytosol fractions prepared from the uterus and hypothalamus of 50--81-day-old female rats undergoing a 4-day oestrous cycle. In the uterus, the content of nuclear receptor fluctuated in concert with known cyclic changes in the secretion of oestrogen, being maximal at pro-oestrus. Over the period of 50--81 days, the nuclear content at all phases increased with age, again corresponding to known age-related increases in ovarian secretion of oestrogen. This age-related increase in nuclear content, averaged from the values of the different phases in each age group, was related to equivalent increases in uterine wet weight, an increase of 1 pmol of receptor being accompanied by an increase of 80--90 mg. The concentration of cytosol receptor was maintained constant, with respect to wet weight, throughout the cycle and with age, irrespective of changes in nuclear content. In the uterus of normal mature females, translocation of receptor into the nucleus did not lead to depletion of cytosol receptor, suggesting a process of continuous replenishment/synthesis. In the hypothalamus, the nuclear content of oestrogen receptor was also maximal at pro-oestrus. In contrast with the uterus, the content of hypothalamic cytosol receptor was minimal at this phase and reflects depletion of the cytosol receptor, possibly as a result of translocation. The extent of translocation was low compared with that in the uterus and did not alter with age during the age-period studied. This low nuclear binding of the receptor in vivo is discussed in relation to the presence of a cytosol factor, present in limiting amounts, which in vitro mediates the binding of cytosol receptor to oligo(dT)-cellulose. The difference in the physiological response of the uterus and of the hypothalamus to oestrogens may be related to the extent of nuclear binding of receptor.
对处于4天发情周期的50至81日龄雌性大鼠的子宫和下丘脑制备的细胞核和胞质溶胶组分中的特异性雌激素受体进行了同步测量。在子宫中，细胞核受体的含量与已知的雌激素分泌周期性变化一致波动，在动情前期达到最大值。在50至81天期间，所有阶段的细胞核含量均随年龄增加，这再次与已知的卵巢雌激素分泌随年龄增加相对应。每个年龄组不同阶段的值平均得出的这种与年龄相关的细胞核含量增加，与子宫湿重的相应增加有关，受体增加1皮摩尔伴随着80至90毫克的增加。胞质溶胶受体的浓度相对于湿重，在整个周期和随年龄变化中保持恒定，与细胞核含量的变化无关。在正常成熟雌性的子宫中，受体向细胞核的转运不会导致胞质溶胶受体的消耗，这表明存在持续补充/合成的过程。在丘脑中，雌激素受体的细胞核含量在动情前期也最高。与子宫相反，下丘脑胞质溶胶受体的含量在此阶段最低，这反映了胞质溶胶受体的消耗，可能是转运的结果。与子宫相比，转运程度较低，并且在所研究的年龄期间不随年龄变化。本文讨论了体内受体这种低细胞核结合与一种胞质溶胶因子的存在有关，该因子含量有限，在体外介导胞质溶胶受体与寡聚（dT）-纤维素的结合。子宫和下丘脑对雌激素的生理反应差异可能与受体的细胞核结合程度有关。
