Wilson D B, Christensen E
J Anat. 1981 Oct;133(Pt 3):407-17.
The differentiation of somatotrophs and mammotrophs in the pars distalis of dwarf (dw/dw) and normal (+/+; dw/+) litter mates was studied by means of electron microscopy from the day of birth to 24 days, as well as in adults at 3-4 months of age. On the basis of a combination of growth measurements, including weight, total body length, and tail length, dwarfs were identifiable with certainty as early as 5 days in litters from heterozygous matings (dw/+ x dw/+). Newborn dwarfs were obtained from homozygous matings (dw/dw x dw/dw) of adult dwarfs which had been brought to sexual maturity by hormone supplementation. The results indicate that the dwarf pituitary is already abnormal at birth. In contrast to the pars distalis in the normal newborn mouse, somatotrophs and mammotrophs cannot be distinguished from one another nor can they be distinguished as a group from other cell types in the dwarf. However, as development progresses, the dwarfs show a large population of an ambiguous somatotroph-mammotroph-like cell with fine structural characteristics of both somatotrophs and mammotrophs; these ambiguous cells also occur in the 3-4 months old adult.
通过电子显微镜研究了侏儒（dw/dw）和正常（+/+；dw/+）同窝幼崽远侧部生长激素细胞和催乳激素细胞从出生到24天的分化情况，以及3 - 4月龄成年动物的情况。基于包括体重、全身长度和尾巴长度在内的生长测量结果的综合分析，早在杂合交配（dw/+×dw/+）的窝中出生5天时，就可以确定地识别出侏儒。新生侏儒是从通过激素补充达到性成熟的成年侏儒的纯合交配（dw/dw×dw/dw）中获得的。结果表明，侏儒垂体在出生时就已经异常。与正常新生小鼠的远侧部不同，侏儒的生长激素细胞和催乳激素细胞彼此无法区分，也无法作为一个群体与其他细胞类型区分开来。然而，随着发育的进行，侏儒表现出大量具有生长激素细胞和催乳激素细胞精细结构特征的模糊的生长激素 - 催乳激素样细胞；这些模糊细胞也出现在3 - 4月龄的成年动物中。
