NUTRITION AND REGULATION OF POSTPARTUM ANOVULATION

产后无排卵的营养和调节

• 批准号: 3330243
• 负责人: KATHLEEN M RASMUSSEN
• 金额: $ 14.87万
• 依托单位: CORNELL UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-08-01 至 1995-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3330243
• 关键词: bromocriptine; developmental nutrition; dietary supplements; endocrine pharmacology; endogenous opioid; fertility; follicle stimulating hormone; gonadotropin releasing factor; gonadotropins; hormone regulation /control mechanism; hypothalamic pituitary axis; infant animal; laboratory rat; lactation; luteinizing hormone; malnutrition; menstrual cycle disorder; naloxone; nutrition related tag; ovariectomy; ovulation; pituitary gonadal axis; pregnancy; prolactin

The mechanisms by which lactation and malnutrition inhibit ovulation are important medically and have significant demographic implications. The experiments proposed here are the first to utilize the ovariectomized rat as an animal model for studying the independent and synergistic effects of chronic undernutrition and suckling on the modulation of prolactin and gonadotropin release during lactation. Experiment 1 will examine the effects of litter size and dietary restriction on the control of luteinizing hormone (LH), follicle stimulating hormone (FSH) and prolactin release from the pituitary. This experiment will utilize a 3 x 3 factorial design with dietary intake (ad libitum, 85% ad libitum, and 70% ad libitum) and litter size (2, 5, and 8 pups) as the main factors. It is hypothesized that both dietary restriction and increased litter size will independently and synergistically influence circulating LH, FSH and prolactin concentrations. Furthermore, we expect both main factors to independently and interactively result in depressed responsiveness to gonadotropin releasing hormone (GnRH) as measured by plasma LH and FSH responses to GnRH challenge. Maternal and pup behavior will also be documented and used in regression analyses to predict plasma hormone concentrations. Experiment 2 will study the effect of food supplementation on gonadotropin release and pituitary responsiveness to GnRH as well as prolactin concentrations. We hypothesize that LH, FSH and prolactin concentrations will be increased in food-restricted lactating animals when refed. Again, the effects of dietary regimen on dam and litter behavior will be assessed. Experiment 3 will examine the effect of an opioid antagonist (naloxone) or prolactin inhibiting factor (bromocriptine) on plasma LH concentrations in lactating ad libitum-fed and food-restricted rats. Both well -fed and chronically undernourished, ovariectomized lactating rats will be treated with either naloxone, bromocriptine, naloxone and bromocriptine, or saline. The effect of nutritional status and drug treatment on plasma LH concentrations and responsiveness to GnRH will be determined in early (d 10) and peak (d 14) lactation. It is hypothesized that endogenous opioids contribute more to hypothalamic suppression during malnutrition than does the dopaminergic pathway. In summary, these experiments will provide incisive information concerning the physiological mechanisms by which lactation, undernutrition and suckling. characteristics interact and influence the hypothalamic-pituitary-ovarian axis.

泌乳和营养不良抑制排卵的机制是 在医学上重要，具有重大的人口影响。 这 这里提出的实验是第一个使用卵巢切除的大鼠的实验 作为研究独立和协同作用的动物模型 慢性营养不良和哺乳的催乳素和哺乳 哺乳期间的促性腺激素释放。 实验1将检查 垃圾大小和饮食限制对控制的影响 黄体生成激素（LH），卵泡刺激激素（FSH）和 催乳素从垂体释放。 该实验将使用3 X 3阶乘饮食摄入量的阶乘设计（自由摄入，85％，自意和 主要因素为70％和垃圾大小（2、5和8幼崽）。 假设饮食限制和增加的垃圾 大小将独立和协同影响循环LH，FSH 和催乳素浓度。 此外，我们期望这两个主要因素 独立和互动导致对 通过血浆LH和FSH测量的促性腺激素释放激素（GNRH） 对GNRH挑战的回应。 母亲和幼犬的行为也将是 记录并用于回归分析以预测血浆激素 浓度。 实验2将研究食物的影响 补充促性腺激素释放和垂体反应性 GnRH以及催乳素浓度。 我们假设LH，FSH 催乳素浓度将在限制食物中升高 饲养时哺乳动物。 同样，饮食方案对 将评估大坝和垃圾行为。 实验3将检查 阿片类药物拮抗剂（纳洛酮）或催乳素抑制因子的作用 （溴o我）在哺乳期喂养的血浆LH浓度上 和限制食物的大鼠。 饮食良好且持续营养不足， 卵巢切除的哺乳动物大鼠将用纳洛酮治疗， 溴ocr诗，纳洛酮和溴封然或盐水。 效果 血浆LH浓度和药物治疗的营养状况和药物治疗 对GNRH的响应将在早期（D 10）和峰（D 14）中确定 哺乳。 假设内源性阿片类药物会贡献更多 在营养不良期间下丘脑抑制 多巴胺能途径。 总而言之，这些实验将提供 有关生理机制的敏锐信息 哺乳，营养不良和哺乳。特征相互作用 影响下丘脑 - 垂体 - 卵巢轴。