Ramp W K, Lenz L G, Kaysinger K K
Baxter Orthopaedic Research Laboratory, Department of Orthopaedic Surgery, Carolinas Medical Center, Charlotte, NC 28232-2861.
Bone Miner. 1994 Jan;24(1):59-73. doi: 10.1016/s0169-6009(08)80131-6.
The effects of medium pH were tested on calvariae, tibiae, and osteoblast-like cells from chick embryos. Bones and isolated cells were incubated for 5 h or 2 days in Hepes-buffered medium at pH values ranging from 6.8 to 8.2. Osteoblast function was evaluated by lactate production, oxygen consumption, alkaline phosphatase activity (AlPase), Ca and inorganic phosphate (Pi) flux, proline hydroxylation, DNA content, and thymidine incorporation. As medium pH was increased, glycolysis, collagen synthesis, and AlPase increased, while Ca efflux decreased. No effect of pH was seen on mitochondrial activity, Pi efflux, or cell number or proliferation. The importance of glycolysis as an endogenous pH regulator was demonstrated by inhibition with iodoacetic acid or glucose restriction and by adding lactate to the medium. The results suggest that the pH of bone interstitial fluid may be regulated by glycolysis and that changes in pH of this compartment may have marked effects on osteoblast function.
研究了培养基pH值对鸡胚颅骨、胫骨和成骨样细胞的影响。将骨骼和分离出的细胞在pH值为6.8至8.2的Hepes缓冲培养基中孵育5小时或2天。通过乳酸生成、耗氧量、碱性磷酸酶活性（AlPase）、钙和无机磷酸盐（Pi）通量、脯氨酸羟化、DNA含量和胸苷掺入来评估成骨细胞功能。随着培养基pH值升高，糖酵解、胶原蛋白合成和AlPase增加，而钙外流减少。未观察到pH值对线粒体活性、Pi外流、细胞数量或增殖有影响。通过碘乙酸抑制或葡萄糖限制以及向培养基中添加乳酸，证明了糖酵解作为内源性pH调节剂的重要性。结果表明，骨间质液的pH值可能受糖酵解调节，并且该隔室pH值的变化可能对成骨细胞功能产生显著影响。
