Paul S, Jailkhani B L
J Reprod Fertil. 1982 Nov;66(2):445-50. doi: 10.1530/jrf.0.0660445.
Purified human placental syncytiotrophoblast consistently failed to bind specifically to 125I-labelled hCG. Treatment of the syncytiotrophoblast with neuraminidase resulted in the ability to bind 125I-labelled hCG that was displaceable by excess of unlabelled hCG. Neuraminidase treatment removed 73.8% of the total neuraminic acid of syncytiotrophoblast. The specific binding of 125I-labelled hCG increased linearly with increasing amount of neuraminidase-treated syncytiotrophoblast, was saturable and had a Ka = 1.6 x 10(7) M-1. Excess of GH, prolactin, placental lactogen or insulin did not inhibit the binding, whereas LH did so completely and FSH partly.
纯化的人胎盘合体滋养层细胞始终无法特异性结合125I标记的hCG。用神经氨酸酶处理合体滋养层细胞后，其获得了结合125I标记hCG的能力，且这种结合可被过量的未标记hCG所取代。神经氨酸酶处理去除了合体滋养层细胞中73.8%的总神经氨酸。125I标记hCG的特异性结合随着神经氨酸酶处理的合体滋养层细胞数量增加而呈线性增加，具有饱和性，解离常数Ka = 1.6×10(7) M-1。过量的生长激素、催乳素、胎盘催乳素或胰岛素不会抑制这种结合，而促黄体生成素会完全抑制，促卵泡生成素则部分抑制。
