Moya F, Glaser L
J Biol Chem. 1980 Apr 25;255(8):3258-60.
The rate of transport of alpha-aminoisobutyric acid (AIB) has been measured in Swiss 3T3 cells at different cell densities in the range 10(3) to 5 x 10(4) cells/cm2. There is a pronounced increase in the rate of Na+-dependent AIB uptake below 4 x 10(3) cells/cm2, which can be observed both in growing cells (10% serum) or in cells arrested early in the G1 (G0) portion of the cell cycle in medium containing plasma-derived serum. The rate of AIB transport of cells arrested in G0 can be inhibited by the addition of a plasma membrane-enriched fraction prepared from 3T3 cells. The results are interpreted in terms of two elements that control the rate of AIB transport, one dependent on the position in the cell cycle and the other on cell contact. Preliminary observations suggest that BALB 3T3 cells behave in a similar way.
已在瑞士3T3细胞中测量了α-氨基异丁酸（AIB）在10³至5×10⁴个细胞/cm²范围内不同细胞密度下的转运速率。在低于4×10³个细胞/cm²时，Na⁺依赖性AIB摄取速率显著增加，这在生长细胞（10%血清）或处于细胞周期G1（G0）早期停滞阶段且含有血浆衍生血清的培养基中的细胞中均能观察到。添加从3T3细胞制备的富含质膜的组分可抑制停滞在G0期的细胞的AIB转运速率。结果从控制AIB转运速率的两个因素来解释，一个取决于细胞周期中的位置，另一个取决于细胞接触。初步观察表明BALB 3T3细胞表现出类似的行为。
