Helbig H, Korbmacher C, Nawrath M, Erb C, Wiederholt M
Institut für Klimische Physiologie, Klinikum Steglitz der Freien Universität Berlin, FRG.
Curr Eye Res. 1989 Jun;8(6):595-8. doi: 10.3109/02713688908995759.
Uptake of 22Na+ was studied in cultured bovine pigmented ciliary epithelial cells (PE) in HCO3-containing media. Two components of Na+-uptake were stimulated by intracellular acidification (NH4+-prepulse): One was amiloride-sensitive, the other DIDS-sensitive. The amiloride-sensitive component of Na+-uptake probably represents Na+/H+-exchange, which has previously been characterized in PE. The second, DIDS-sensitive component stimulated by intracellular acidification, was Cl- and HCO3--dependent. We conclude that a stilbene-sensitive, Cl--dependent Na+-HCO3--cotransport is present in PE. This transport could play an important role in aqueous humor formation.
在含有HCO₃⁻的培养基中，对培养的牛色素性睫状上皮细胞（PE）摄取²²Na⁺的情况进行了研究。细胞内酸化（NH₄⁺预脉冲）刺激了Na⁺摄取的两个成分：一个对氨氯吡脒敏感，另一个对4,4'-二异硫氰基-2,2'-二磺酸芪（DIDS）敏感。Na⁺摄取的氨氯吡脒敏感成分可能代表Na⁺/H⁺交换，此前已在PE中得到表征。细胞内酸化刺激的第二个对DIDS敏感的成分依赖于Cl⁻和HCO₃⁻。我们得出结论，PE中存在一种对二苯乙烯敏感、依赖于Cl⁻的Na⁺-HCO₃⁻协同转运体。这种转运可能在房水形成中起重要作用。
