Tuan R S
J Embryol Exp Morphol. 1983 Apr;74:119-31.
It was previously reported (Tuan, 1980a) that the development-specific expression of calcium transport and related functions in the chick embryonic chorioallantoic membrane (CAM) requires the continuous presence of the eggshell, the calcium source of the embryo. To further understand the mechanism of action of the eggshell on the CAM functions, this study reports the effects of eggshell supplementation on chick embryos maintained in shell-less cultures. The cultured embryos were able to accumulate and utilize the exogenous shell calcium, applied directly onto the CAM, for skeletal formation. In the region of the CAM directly adhering to the added shell, calcium transport activity, calcium-binding protein (CaBP) activity, and vitamin K-dependent gamma-glutamyl carboxylase activity were significantly restored. These results strongly suggest that the proximity of shell calcium may regulate expression of calcium transport and related functions in the chick embryonic CAM.
此前有报道（Tuan，1980a）称，鸡胚绒毛尿囊膜（CAM）中钙转运及相关功能的发育特异性表达需要蛋壳（胚胎的钙源）持续存在。为进一步了解蛋壳对CAM功能的作用机制，本研究报告了补充蛋壳对无壳培养的鸡胚的影响。培养的胚胎能够积累并利用直接施加于CAM上的外源蛋壳钙用于骨骼形成。在CAM直接附着于添加蛋壳的区域，钙转运活性、钙结合蛋白（CaBP）活性和维生素K依赖的γ-谷氨酰羧化酶活性显著恢复。这些结果有力地表明，蛋壳钙的接近可能调节鸡胚CAM中钙转运及相关功能的表达。
