Fullerton M J, Smith A I, Funder J W
Medical Research Centre, Prince Henry's Hospital, Melbourne, Australia.
Neuroendocrinology. 1988 Jan;47(1):1-6. doi: 10.1159/000124882.
The pituitary and hypothalamic content of dynorphin was determined by radioimmunoassay and characterized by high-performance liquid chromatography (HPLC) in adult female Sprague-Dawley rats, intact and ovariectomized with and without estrogen treatment. Animals were given estradiol benzoate, or vehicle (oil) by six daily intramuscular injections. Anterior pituitary content of immunoreactive (ir)-dynorphin in ovariectomized rats was approximately twice that of intact animals, and consisted of a single HPLC peak co-eluting with dynorphin 32. Administration of estradiol benzoate (0.06-6 micrograms/day) caused a marked decrease of ir-dynorphin in the anterior lobe of castrate female rats, with a half-maximal effect at 0.2 microgram/day; levels were restored to those seen in intact animals with 6 micrograms estradiol benzoate per day, an effect which was not influenced by concomitant administration of progesterone (1 mg/day), or bromocriptine (100 micrograms/day). In the hypothalamus and neuro-intermediate lobe multiple peaks of immunoreactive dynorphin were seen, coeluting with dynorphin A 1-8, dynorphin A 1-17 and dynorphin 32. Neither castration nor estrogen treatment altered ir-dynorphin content in these tissues. These findings suggest that the ovary exerts a specific modulating influence on AP ir-dynorphin in the rat, and that in addition this inhibition appears to be mediated by ovarian estrogen.
采用放射免疫分析法测定成年雌性斯普拉格-道利大鼠（完整的以及去卵巢且接受或未接受雌激素治疗的）垂体和下丘脑内强啡肽的含量，并通过高效液相色谱法（HPLC）进行特性分析。通过每日6次肌肉注射给予动物苯甲酸雌二醇或赋形剂（油）。去卵巢大鼠垂体前叶中免疫反应性（ir）-强啡肽的含量约为完整动物的两倍，且由与强啡肽32共洗脱的单一HPLC峰组成。给予苯甲酸雌二醇（0.06 - 6微克/天）可使去势雌性大鼠前叶中的ir-强啡肽显著降低，在0.2微克/天时达到半数最大效应；每天给予6微克苯甲酸雌二醇可使水平恢复至完整动物的水平，该效应不受同时给予孕酮（1毫克/天）或溴隐亭（100微克/天）的影响。在下丘脑和神经中间叶可见免疫反应性强啡肽的多个峰，与强啡肽A 1 - 8、强啡肽A 1 - 17和强啡肽32共洗脱。去势和雌激素治疗均未改变这些组织中的ir-强啡肽含量。这些发现表明，卵巢对大鼠垂体前叶ir-强啡肽具有特定的调节作用，此外这种抑制作用似乎由卵巢雌激素介导。
