奶源在大鼠毛细管管和乳脂肪含量Creamatocrit估计
Summary
Milk is a primary source of nutrition for the neonate. Analysis of milk components may provide insight into maternal factors that affect offspring health. This protocol describes a manual method of collecting milk samples from the lactating rat, which can then be used for further downstream analysis.
Abstract
Milk, as the sole source of nutrition for the newborn mammal, provides the necessary nutrients and energy for offspring growth and development. It also contains a vast number of bioactive compounds that greatly affect the development of the neonate. The analysis of milk components will help elucidate key factors that link maternal metabolism and health with offspring growth and development. The laboratory rat represents a popular model organism for maternal studies, and rat milk can be used to examine the effect of various maternal physiological, nutritional, and pharmacological interventions on milk components, which may then impact offspring health. Here a simple method of manually collecting milk from the lactating rat that can be performed by a single investigator, does not require specialized vacuum or suction equipment, and provides sufficient milk for subsequent downstream analysis is described. A method for estimating the fat content of milk by measuring the percentage of cream within the milk sample, known as the creamatocrit, is also presented. These methods can ultimately be used to increase insight into maternal-child health and to elucidate maternal factors that are involved in proper growth and development of offspring.
Introduction
牛奶是营养新生哺乳动物，对于婴儿生长发育1,2-提供能量和营养的唯一来源。而乳主要由细胞脂质和蛋白 1，它还包含了过多了调节后代生命早期发展，包括酶，碳水化合物，激素，抗体，生长因子，细胞因子，外来体，微泡，和小RNA这样的生物活性化合物的作为微小RNA 1,2。孕妇奶粉在建立后代免疫和肠道健康3中的基础性作用，再加上证据表明，母乳喂养的婴儿不易受疾病2，突出了识别与疾病过程的早期生活有关的牛奶成分和所涉及的分子机制的重要性在他们的行动。发育大鼠是一种流行调查的各种营养，生理效果模型，并在早期的化学干预-生命的发展4。因此，大鼠乳汁的分析可以提供新的洞察孕产妇和后代的健康。
目前的科学进步，现在提供了越来越多的深入调查，对健康和疾病的特定的牛奶成分的影响的机会。例如，牛奶细菌型材测序阐明在婴儿肠道5早期肠集群自己的角色，乳寡糖的质谱分析已通过母亲饮食6，和微小RNA的深度测序分泌提供的洞察的乳寡糖概况的改变母乳的脂肪球突出于基因转录，代谢和免疫功能7可能角色。
大鼠模型代表在产妇的研究8,9中最常用的模式生物之一。一个优点是其短怀孕期和哺乳期的，仅approximat伊利21天每一个;因此，从怀孕哺乳的开始的总时间表示短时间内在能够产生有价值的数据。大鼠的较大尺寸相比小鼠，在奶源的背景下，可提供相对于牛奶和易于奶源体积显著优势;牛奶产量的小鼠，例如，似乎是依赖于总体重以产生更多的奶10较重的小鼠。
在这里，提供了手动收集的牛奶哺乳大鼠的一般描述。此协议需要最少的设备，非侵入性的，廉价的，并且可以用于收集奶足够量用于进一步下游分析。简言之，大坝用异氟烷麻醉，放乳由催产素的刺激，以及牛奶通过牛奶手册表达收集到毛细管。最后，如牛奶两个主要组成部分是脂肪和蛋白质，简要DESCRIPTIOÑ 估计使用creamatocrit测量11和使用标准蛋白质测定总蛋白质浓度的定量乳脂肪含量的呈现。
Protocol
Representative Results
Discussion
Investigations into maternal milk components have increased as interest in early life development research rises. As the sole source of nutrition during the neonatal period, the bioactive compounds in milk are essential for ideal growth and development, especially in the context of intestinal and immune health3. The method presented here is a simple, non-invasive method of collecting milk from the lactating rat in amounts sufficient for downstream analysis, such as oligosaccharide profiling6. The me…
Disclosures
The authors have nothing to disclose.
Acknowledgements
这个作品是通过从加拿大自然科学和工程研究委员会（RGPIN 238382-2011）和健康研究（MOP115076）的加拿大学院资助。希瑟·保罗是由加拿大自然科学和工程研究理事会研究生奖学金和艾伯塔创新的健康解决方案的奖学金支持。梅根·哈勒姆是由自然科学与工程研究理事会研究生奖学金，一个弗雷德里克·班廷和查尔斯最佳加拿大研究生奖学金，和亚省儿童医院研究所培训奖遗传学，儿童发展，健康的支持。
Materials
| Equipment – Milking | |||
| 1 ml syringes | BD-Canada | 309602 | |
| 25 G needles | BD-Canada | 305122 | |
| 18 G needles | BD-Canada | 305196 | |
| 50 ul Microdispenser Capillary Tubes | Fisher Scientific | 21-169D | |
| Oxytocin (20 USP Units/ml) | Bimeda-MTC | 1OXY015 | |
| PPC Vet Isoflurane Inhalation Anesthetic, 250 ml | Fresenius Kabi | M60302 | Used on the order of a veterinarian |
| Sterile Alcohol Prep Pad | Dukal | 853 | |
| Absorbent Bench Underpad | VWR | 82020-845 | |
| Maxi-Therm Hyper/Hypothermia Blanket | Cincinnati Sub-Zero | 274 | |
| Rodent Anesthesia Machine with Vaporizer | Benson Medical Industries Inc. | Subject to individual laboratory needs | |
| Animal Masks | Benson Medical Industries Inc. | 50100/50102 | |
| Microcentrifuge Tubes | Axygen | MCT-060-C | |
| ChroMini Professional Trimmer | Wahl | – | |
| Equipment – Creamatocrit | |||
| StatSpin SafeCrit Plastic Microhematocrit Tubes (Untreated) | Fisher Scientific | 22-274-914 | |
| Critoseal Capillary Tube Sealant Tray | VWR | 470161-478 | |
| StatSpin CritSpin Microhematocrit Centrifuge | Beckman Coulter, Inc | X00-004999-001 |
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