【摘要】 作者用匀浆、超声波及蔗糖密度梯度离心法制备了卵巢细胞膜,较单纯匀浆之HCG结合率提高1750倍,四种蔗糖浓度及五种蔗糖浓度之分离效果对比,以前者为宜,离心速度为78000×g时结合率最高,且集中于33％表面层及33％～37％界面层。更多还原

【Abstract】 It has been documented that the ovariancell membrane has specific HCG receptors.The isolation and characterization of theovarian cell membrane have been studied. Rat ovaries are homogenized and sonicedunder ice-cold conditions. The homogenatesare centrifuged at 2000×g for 15 min. Aftersucrose density gradient ultracentrifugation(78000×g, 4h), two fractions are collectedfrom layer of 33% and interface between 33%and 37%. The membrane layer is taken outand washed free of sucrose by centrifugationat 39000×g for 1h. The pellets are suspendedin an appropriate: amount of 40 mM Trisbuffer. In comparison with homogenates andsonicates, the activity of 5-nucleotidase ofplasma membrane increases ten times. HCGreceptor binding of the plasma membrane is1750 times as high as the homogenates andsonicates. Preparations are checked by elec-tron microscopy. Nuclei, mitochondria,lysomes, rough microsomes and Golgimembranes are absent from most of thepreparations. The separation at the four sucrose con-centrations (33%, 37%, 41%, 45%) is more effec-tive than at the five sucrose concentrations(33%, 37%, 41%, 45%, 48%). The centrifugespeed (78000×g) is the optimum speed.更多还原