Cells of in vitro cultured epidermis explants of ectoderm isolated at early gastrula stage,showed only weak excitability or even non-excitable at 6V when examined electrophysiologically.If non-excitable explants were ...Cells of in vitro cultured epidermis explants of ectoderm isolated at early gastrula stage,showed only weak excitability or even non-excitable at 6V when examined electrophysiologically.If non-excitable explants were treated with 100 mM glucose,the action potential (AP) appeared and within 1 hr reached its maximum.At the same time,their stimulus threshold became lowered gradually.And,if the glucose was washed out,AP gradually disappeared.If explants were treated with glucose of different concentrations,the percentage of explants which displayed AP increased with the increase of glucose concentration.When explants with approximately the same original stimulus threshold were treated with glucose of different concentrations,the stimulus threshold became lowered more in the more concentrated solution.If explants with different original stimulus thresholds were treated with glucose of the same concentration,the lowering of stimulus threshold was more obvious in those with higher original stimulus threshold.Other energy supplying substances used showed similar effect.展开更多
The target molecule of monoclonal antibody AA98 (AA for short) is a new vascular endothelial cell related factor and plays a role in angiogenesis as indicated by the previous data. To investigate its role in angiogene...The target molecule of monoclonal antibody AA98 (AA for short) is a new vascular endothelial cell related factor and plays a role in angiogenesis as indicated by the previous data. To investigate its role in angiogenesis and placentation in primate, we examined its expression in the implantation sites on D17, 19, 28 and 34 of gestation in rhesus monkey by immunohistochemistry and Western immunoblot. Western blot analysis showed that the primary antibody used in this study was specific for its epitope. AA protein was mainly expressed in small blood vessels and in some cytotrophoblast cells. The AA staining was found mainly in the endothelial cells and vascular small muscle.This observation supported the AA's role in angiogenesis. AA was spatio-temporarily expressed in cytotrophoblasts: weak in proliferating trophoblast within cell column and endovascular trophoblast, strong in trophoblastic subpopulation within the basal plate and vascular trophoblast; AA staining within the basal plate was down-regulated during early placentation. The shift of AA98 expression in extravillous trophoblasts suggestes a role of this new factor during the course of cytotrophoblast metastasis and spiral artery remodeling. The spatio-temporarily expression indicats that AA98 could be also used as a trophoblast cellular marker to characterize the acquisition of a vascular endothelial and invasive phenotype.展开更多
文摘Cells of in vitro cultured epidermis explants of ectoderm isolated at early gastrula stage,showed only weak excitability or even non-excitable at 6V when examined electrophysiologically.If non-excitable explants were treated with 100 mM glucose,the action potential (AP) appeared and within 1 hr reached its maximum.At the same time,their stimulus threshold became lowered gradually.And,if the glucose was washed out,AP gradually disappeared.If explants were treated with glucose of different concentrations,the percentage of explants which displayed AP increased with the increase of glucose concentration.When explants with approximately the same original stimulus threshold were treated with glucose of different concentrations,the stimulus threshold became lowered more in the more concentrated solution.If explants with different original stimulus thresholds were treated with glucose of the same concentration,the lowering of stimulus threshold was more obvious in those with higher original stimulus threshold.Other energy supplying substances used showed similar effect.
基金This work was supported by the WHO/Rockefeller Fundation(Grant No.RF96020#78)the Knowledge Innovation Program of CAS(Grant No.KSCX-2-SW-201)+1 种基金the National“973”Program(Grant No.G1999055901)the National Natural Science Foundation of China(Grant No.30270196)
文摘The target molecule of monoclonal antibody AA98 (AA for short) is a new vascular endothelial cell related factor and plays a role in angiogenesis as indicated by the previous data. To investigate its role in angiogenesis and placentation in primate, we examined its expression in the implantation sites on D17, 19, 28 and 34 of gestation in rhesus monkey by immunohistochemistry and Western immunoblot. Western blot analysis showed that the primary antibody used in this study was specific for its epitope. AA protein was mainly expressed in small blood vessels and in some cytotrophoblast cells. The AA staining was found mainly in the endothelial cells and vascular small muscle.This observation supported the AA's role in angiogenesis. AA was spatio-temporarily expressed in cytotrophoblasts: weak in proliferating trophoblast within cell column and endovascular trophoblast, strong in trophoblastic subpopulation within the basal plate and vascular trophoblast; AA staining within the basal plate was down-regulated during early placentation. The shift of AA98 expression in extravillous trophoblasts suggestes a role of this new factor during the course of cytotrophoblast metastasis and spiral artery remodeling. The spatio-temporarily expression indicats that AA98 could be also used as a trophoblast cellular marker to characterize the acquisition of a vascular endothelial and invasive phenotype.
