Bustamante J C, Yudilevich D L, Boyd C A
Department of Physiology, King's College, London.
Q J Exp Physiol. 1988 Nov;73(6):1013-6. doi: 10.1113/expphysiol.1988.sp003212.
Sulphate transport into and out of membrane vesicles prepared from both the brush-border and basal surfaces of the human placental trophoblast has been studied. For both surfaces of this epithelium clear evidence of trans-stimulation of influx is seen but for efflux, acceleration of labelled sulphate movement by addition of external sulphate is seen only in basal and not in brush-border membrane vesicles. This kinetic asymmetry may underlie the previously observed, but unexplained, finding that the concentration of sulphate is greater in the fetal than in the maternal circulation.
对从人胎盘滋养层的刷状缘和基底表面制备的膜囊泡中硫酸盐的进出转运进行了研究。对于该上皮细胞的两个表面，均观察到了跨刺激流入的明确证据，但对于流出，仅在基底膜囊泡而非刷状缘膜囊泡中观察到添加外部硫酸盐会加速标记硫酸盐的移动。这种动力学不对称可能是先前观察到但未得到解释的现象的基础，即胎儿循环中硫酸盐的浓度高于母体循环中的浓度。
