Delehaye M C, Cohen R, Segond N, Pidoux E, Treilhou-Lahille F, Milhaud G, Moukhtar M S
U 113 INSERM, Paris, France.
Biochem Biophys Res Commun. 1989 Mar 15;159(2):528-35. doi: 10.1016/0006-291x(89)90025-9.
The aging WAG/Rij rats (a Wistar derived strain) develop spontaneously medullary thyroid carcinoma with a high frequency (50%). We have studied calcitonin biosynthesis in Wistar and WAG/Rij rats strains in order to determine if early changes in this parameter occurred in the WAG/Rij strain. Thyroidal and plasma CT levels were measured in three months old WAG/Rij and Wistar rats before and after acute calcium challenge. Total RNA was extracted from thyroid glands and specific CT messenger RNA levels estimated by dot and Northern blot analysis with a 32P-labeled probe specific for CT mRNA. The capacity of mRNA to direct synthesis of CT precursor was also measured by translation in an in vitro system. Though mean basal circulating CT levels were equivalent in both strains, CT release after calcium stimulation was much increased in the WAG/Rij rat. CT content of the glands and CT mRNA levels were two fold higher in the WAG/Rij strain. Thus, in this strain, CT biosynthesis and secretion were increased long before the development of a C-cell carcinoma.
衰老的WAG/Rij大鼠（源自Wistar品系）会自发地以高频率（50%）发生甲状腺髓样癌。我们研究了Wistar和WAG/Rij大鼠品系中降钙素的生物合成，以确定该参数的早期变化是否发生在WAG/Rij品系中。在急性钙刺激前后，对3个月大的WAG/Rij和Wistar大鼠的甲状腺和血浆降钙素水平进行了测量。从甲状腺中提取总RNA，并用针对降钙素mRNA的32P标记探针通过斑点杂交和Northern印迹分析来估计特异性降钙素信使RNA水平。mRNA指导降钙素前体合成的能力也通过体外翻译系统进行了测量。尽管两个品系的平均基础循环降钙素水平相当，但WAG/Rij大鼠在钙刺激后的降钙素释放显著增加。WAG/Rij品系的腺体降钙素含量和降钙素mRNA水平高出两倍。因此，在该品系中，降钙素的生物合成和分泌在C细胞癌发生之前很久就增加了。
