SEX HORMONE EFFECTS ON INTESTINAL CALCIUM ABSORPTION

这项研究的目的是确定女性激素的作用 肠道钙吸收状况。 钙的肠道吸收是 在几种生理状态中发生改变，这些状态也与 循环性激素浓度的变化，如性激素， 成熟、怀孕、哺乳和衰老。 三个系列实验 已经被设计来测试雌激素 可调节肠道钙吸收。 首先，实验将 研究雌激素是否直接或间接影响 肠道钙吸收。 这些研究将在两个 成熟的，周期性的雌性大鼠和年轻的，成熟的雌性大鼠， 确定性激素对肠道成熟过程的可能影响 以及成熟的肠。 外翻肠囊的钙转运 十二指肠和其他肠段将与循环 Ca、P、雌二醇和孕酮的浓度。 催乳素， 甲状旁腺激素和降钙素也将在一些测量 实验 这些参数将在卵巢切除的 (ovx)低钙组（0.02%）和正常钙组（0.50%）。 激素替代和克罗米酚和溴隐亭的药物治疗 将被用来确定雌激素是否对 肠道钙转运，如果不是，直接效应物是什么。 的 第二系列实验旨在确定 由于自然发生的性别改变导致的肠钙吸收 怀孕期间的激素，哺乳期，性成熟， 发情周期和衰老。 动物经历这些过程将被喂养 无论是正常或低钙饮食和研究使用的方法 描述了早期的实验。 最后一组建议 实验将确定性激素是否影响肠道钙离子 吸收是通过维生素D代谢，肠肥大， 或与细胞Ca转运过程直接相互作用。 的结果 这些实验将增加我们对性激素作用的认识 在调节肠道钙吸收的各种正常生理 性成熟、妊娠、哺乳和绝经等情况 这些都与钙代谢的改变有关。 在 此外，预防和治疗绝经后骨质疏松症将 当我们知道性激素状态对我们的性行为有什么影响时， 肠道钙吸收。

The objective of the research is to determine the effects of female hormone status on the intestinal Ca absorption. The intestinal absorption of Ca is altered in several physiological states that are also associated with changes in circulating sex hormone concentrations such as sexual maturation, pregnancy, lactation and aging. Three series of experiments have been designed to test various aspects of the hypothesis that estrogen can modulate intestinal Ca absorption. First, experiments will be conducted to determine whether estrogen has direct or indirect effects on intestinal Ca absorption. These studies will be carried out in both mature, cycling female rats and in young, maturing females in order to determine possible sex hormone effects on the intestinal maturation process as well as on the mature intestine. Ca transport by everted gut sacs of duodenum and other intestinal segments will be correlated with circulating concentrations of Ca, P, estradiol, and progesterone. Prolactin, parathyroid hormone, and calcitonin will also be measured in some experiments. These parameters will be compared between ovariectomized (ovx) and intact animals on low Ca (O.02%) and normal Ca (0.50%) diets. Hormone replacement and drug treatments with clomiphene and bromocriptine will then be used to determine whether estrogen has a direct effect on intestinal Ca transport or, if not, what the direct effector is. The second series of experiments is designed to determine alterations in intestinal Ca absorption due to naturally occurring alterations in sex hormones during pregnancy, lactation, sexual maturation, various stages of the estrus cycle and aging. Animals undergoing these processes will be fed either the normal or low Ca diet and studied using the methodology described for the earlier experiments. The final group of proposed experiments will determine whether sex hormone effects on intestinal Ca absorption are mediated via vitamin D metabolism, intestinal hypertrophy, or direct interaction with cellular Ca transport processes. The results of these experiments will increase our knowledge of the role of sex hormones in regulating intestinal Ca absorption in a variety of normal physiological conditions such as sexual maturation, pregnancy, lactation, and menopause which are all known to be associated with alterations in Ca metabolism. In addition, the prevention and treatment of postmenopausal osteoporosis will be facilitated when we know what effects sex hormone status has on intestinal Ca absorption.