Nieto Ana I, Shyamala G, Galvez Jose J, Thordarson Gudmundur, Wakefield Lalage M, Cardiff Robert D
Departamento de Patologia Animal II, Facultad de Veterinaria, Cuidad Universitaria, 28040 Madrid, Spain.
Comp Med. 2003 Aug;53(4):433-8.
The inbred FVB/N mouse strain is widely used for creating transgenic mice. Over the past decade, persistent mammary hyperplasia has been detected in many multiparous FVB/N female mice sent to the University of California, Davis (UCD) Mutant Mouse Pathology Laboratory (MMPL) by a number of different laboratories. However, the experimental details concerning most specimens were not always available. To confirm these empiric findings, experiments were carried out to evaluate the mammary glands of FVB/N mice under controlled conditions. Persistent mammary hyperplasia that related to parity was found. Weeks after their first to fourth pregnancy, 10 FVB/N female mice from the Lawrence Berkeley National Laboratory (LBNL) colony were studied and the mammary glands were evaluated. The percentage of fat pad filled was estimated, using image analysis. Serum samples and the pituitary gland from other FVB/N mice from the LBNL were assayed for prolactin concentration. Multiparous FVB/N females consistently had persistent mammary hyperplasia. Four of seven females in the LBNL colony had hyperplasia after three pregnancies. A few foci of squamous nodules and sporadic carcinomas also were observed. Thus, some FVB/N females may have persistent mammary hyperplasia after three pregnancies without detectable pituitary abnormalities. Mammary carcinomas also may develop sporadically. These background phenotypes must be considered when interpreting the effect of genetic manipulation in FVB/N mice.
近交系FVB/N小鼠品系被广泛用于创建转基因小鼠。在过去十年中，许多不同实验室将多胎FVB/N雌性小鼠送至加利福尼亚大学戴维斯分校（UCD）突变小鼠病理实验室（MMPL）时，检测到持续性乳腺增生。然而，大多数标本的实验细节并非总能获取。为了证实这些经验性发现，开展了实验以在可控条件下评估FVB/N小鼠的乳腺。发现了与产次相关的持续性乳腺增生。对来自劳伦斯伯克利国家实验室（LBNL）种群的10只FVB/N雌性小鼠在其首次至第四次怀孕后的数周进行了研究，并对乳腺进行了评估。使用图像分析估计脂肪垫填充的百分比。对来自LBNL的其他FVB/N小鼠的血清样本和垂体进行催乳素浓度测定。多胎FVB/N雌性小鼠始终存在持续性乳腺增生。LBNL种群中七只雌性小鼠中有四只在三次怀孕后出现增生。还观察到一些鳞状结节灶和散发性癌。因此，一些FVB/N雌性小鼠在三次怀孕后可能出现持续性乳腺增生且无明显的垂体异常。乳腺肿瘤也可能散发性发生。在解释FVB/N小鼠基因操作的效果时，必须考虑这些背景表型。
