Prolactin Release Through Breast Stimulation in Non-lactating Women - Who Does Respond?
试验速览
- 阶段
- 不适用
- 状态
- 招募中
- 入组人数
- 40
- 试验地点
- 2
- 主要终点
- Prolactin release - yes/no
研究概览
简要总结
Prolactin is a multifunctional hormone which acts in different cell types rather than just modulating reproduction and lactation. One additional point is its action on glucose metabolism which is described especially in rodents. Prolactin affects proliferation, survival and insulin production of pancreatic beta cells in animal models. But also in human studies prolactin is linked to insulin action. Low systemic levels of prolactin are associated with increased prevalence of diabetes and while higher levels are associated with higher insulin sensitivity.
Acute metabolic effects of prolactin in young, healthy and non-lactating women should be accessed. Therefore, the induction of a transient increase of circulating prolactin levels is necessary to study the acute effects of this hormone on metabolic processes. This can most likely be achieved in non-pregnant and non-lactating women without pharmacological intervention.
As the main stimulus of prolactin release from the pituitary gland is the mechanical stimulation of the breast / nipple, like a suckling baby, stimulation by a breast pump might trigger prolactin release.
Due to other studies in this field, only a minority of women respond to breast stimulation with an increase in prolactin levels. Therefore, this pilot study will assess if an electric milk pump can stimulate prolactin release in non-lactating women. The second aim of the study is to identify factors which determine response and non-response to breast stimulation.
Prolactin will be measured in blood serum. The primary objective of this study is to identify women in whom a 30-minute breast stimulation causes a marked prolactin release. Response is defined as an increase at least twice the baseline value.
Second outcomes are the quantification and duration of prolactin increase as well as to detect differences in responders and non-responders. Therefore, demographic data as well as anthropometric data will also be assessed. A 10-minute electrocardiography and non-invasive measurement of resting energy expenditure by indirect calorimetry will also be performed. History of menstrual cycle, intake of contraceptive, parity and lactation experience will be recorded. Physical activity level and feeling of hunger will be assessed by questionnaires.
Feeling of hunger, resting energy expenditure, blood pressure, heart rate and body temperature will be assessed repeatedly to register differences before and after stimulation. Blood and urine samples will be assessed for safety.
研究设计
- 研究类型
- Interventional
- 分配方式
- Na
- 干预模型
- Single Group
- 主要目的
- Other
- 盲法
- None
入排标准
- 年龄范围
- 18 Years 至 45 Years（Adult）
- 性别
- Female
- 接受健康志愿者
- 是
入选标准
- •Women, aged between 18 and 45 years
- •premenopausal (women, who had menses at any time in the preceding 24 consecutive months)
- •BMI < 25 kg/m²
- •Ability to understand and voluntarily sign an informed consent document prior to any study related procedures
排除标准
- •Type 1 or Type 2 diabetes
- •Intake of medication which may affect prolactin levels (e.g. Metoclopramide, Methyldopa, opiates, cimetidine), except birth control pill/hormonal contraception known hyperprolactinemia or hyperthyroidism
- •any other serious illness that might impact the results as judged by the investigator (e.g. malignant disease, coronary heart disease)
- •Pregnant / breastfeeding women (weaning at least 6 month ago)
- •plastic breast surgery (with detachment of milk ducts)
- •allergy to BPA-free plastic
结局指标
主要结局
Prolactin release - yes/no
时间窗: Sample collection will be from 0 to 90 minutes
The primary objective of this study is to identify women in whom breast stimulation causes a marked prolactin release. Response is defined as an increase at least twice the baseline blood value.
次要结局
- Differences in subjects age(1 minute)
- Differences in subjects BMI(4 minutes)
- Differences in subjects menstrual cycle phase(2 minutes)
- Differences in subjects heart rate variability parameters: time domain (beats per minute)(10 minutes)
- Differences in subjects body fat content(3 minutes)
- Prolactin levels(Sample collection will be from 0 to 90 minutes)
- Differences in subjects parity(2 minutes)
- Differences in subjects stress reaction(Sample collection will be from 0 to 90 minutes)
- Changes in body temperature through stimulation(1 minute)
- Changes of Hypothalamic-Pituitary-Gonadal axis activity(90 minutes)
- Differences in subjects heart rate variability parameters: Standard deviation of RR-intervals (SDNN)(10 minutes)
- Differences in subjects physical activity level(10 minutes)
- Changes in feelings of hunger through stimulation(10 minutes)
- Changes in heart rate through stimulation(4 minutes)
- Changes of Hypothalamic-Pituitary-Somatotropic axis activity(90 minutes)
- Changes of Hypothalamic-Pituitary-Thyroid axis activity(90 minutes)
- Differences in subjects intake of hormonal contraception(2 minutes)
- Differences in subjects heart rate variability parameters: Root Mean Square of successive RR interval differences (RMSSD)(10 minutes)
- Differences in subjects heart rate variability parameters: Low to high frequency power ratio(20 minutes)
- Changes in blood pressure through stimulation(4 minutes)
- Differences in subjects history of lactation(2 minutes)
- Differences in subjects heart rate variability parameters: frequency domain parameters(10 minutes)
- Changes in resting energy expenditure through stimulation(30 minutes (each 15 minutes))
- Changes of Hypothalamic-Pituitary-Adrenal axis activity(90 minutes)
- Changes of Hypothalamic-Pituitary-Prolactin axis activity(90 minutes)