REGULATION OF BRAIN AROMATASE-ACTIVITY IN RATS
REGULATION OF BRAIN AROMATASE-ACTIVITY IN RATS
复制标题
DOI：
10.1210/endo-114-1-192
复制
发表时间：
1984-01-01
期刊：
影响因子：
4.8
通讯作者：
RESKO, JA
中科院分区：
文献类型：
--
作者：
ROSELLI, CE;ELLINWOOD, WE;RESKO, JA
用灵敏的体外测定法测量在[1 β-D]转化过程中形成的3 H2O的量，在成年大鼠脑中芳香酶活性的分布和调节3 H]雄烯二酮转化为雌酮。下丘脑-视前区（HPOA）中芳香酶活性的速率与时间呈线性关系，直至1小时，并且与组织浓度呈线性关系，直至5 mgeq/200 μ l孵育混合物。该酶的最适pH为7.4，表观Km为0.04 μ M。芳香化酶活性最大的发现在杏仁核和HPOA从完整的雄性大鼠。海马、中脑被盖、大脑皮质、小脑和垂体前叶都含有可忽略的酶活性。去势使HPOA芳香化酶活性显著降低（P < 0.001），但杏仁核和大脑皮质芳香化酶活性无显著变化（P < 0.05）。雄性大鼠的HPOA含有显着更大的芳香化酶活性比雌性大鼠HPOA。在雌性动物中，这种酶的活性在发情周期或卵巢切除术后没有变化。雄性和雌性去势大鼠给予睾酮后，其HPOA芳香化酶活性显著增强（P < 0.05），接近于正常雄性大鼠的水平。显然，睾酮或其代谢产物之一是大鼠HPOA芳香化酶活性的主要甾体调节剂。
The distribution and regulation of aromatase activity in the adult rat brain with a sensitive in vitro assay that measures the amount of 3H2O formed during the conversion of [1.beta.-3H]androstenedione to estrone. The rate of aromatase activity in the hypothalamus-preoptic area (HPOA) was linear with time up to 1 h, and with tissue concentrations up to 5 mgeq/200 .mu.l incubation mixture. The enzyme demonstrated a pH optimum of 7.4 and an apparent Km of 0.04 .mu.M. The greatest amount of aromatase activity was found in amygdala and HPOA from intact male rats. The hippocampus, midbrain tegmentum, cerebral cortex, cerebellum and anterior pituitary all contained negligible enzymatic activity. Castration produced a significant decrease in aromatase activity in the HPOA (P < 0.001), but not in the amygdala or cerebral cortex (P < 0.05). The HPOA of male rats contained significantly greater aromatase activity than the HPOA of female rats. In females, this enzyme activity did not change during the estrous cycle or after ovariectomy. Administration of testosterone to gonadectomized male and female rats significantly enhanced HPOA aromatase activities (P < 0.05) to levels approximating those found in HPOA from intact males. Apparently testosterone, or one of its metabolites, is a major steroidal regulator of HPOA aromatase activity in rats.