Department of Physiology & Pharmacology, Duke University, 27706, Durham, North Carolina.
J Membr Biol. 1970 Dec;3(1):1-13. doi: 10.1007/BF01868002.
Anti-L serum prepared by immunization of a high-potassium-type (HK) (blood type MM) sheep with blood from a low-potassium-type (LK) (blood type ML) sheep contained an antibody which stimulated four- to sixfold K(+)-pump influx in LK (LL) sheep red cells. In long-termin vitro incubation experiments, LK sheep red cells sensitized with anti-L showed a net increase in K(+) after two days of incubation at 37°C, whereas HK-nonimmune (NI)-serum-treated control cells lost K(+). The antibody could be absorbed by LK (LL) sheep red cells but not by HK sheep red cells. Kinetic experiments showed that the concentration of external K(+) ([K(+)]0) required to produce halfmaximum stimulation of the pump ([Na(+)]0=0, replaced by Mg(++)) was the same (0.25 mM) in L-antiserum-treated or untreated LK cells. LK cells with different [K(+)]i (Na(+) replacement) were prepared by the p-chloromercuribenzene sulfonate (PCMBS) method. At [K(+)]0=5 mM, pump influx decreased as [K(+)]i increased from 1 to 70 mM in L-antiserum-treated LK cells, whereas LK cells treated with HK-NI-serum ceased to pump at [K(+)]i=35 mM. Exposure to anti-L serum produced an almost twofold increase in the number of pump sites of LK cells as measured by the binding of tritiated ouabain by LK sheep red cells. These findings indicate that the formation of a complex between the L-antigen and its antibody stimulates active transport in LK sheep red cells both by changing the kinetics of the pump and by increasing the number of pump sites.
用低钾型（LK）（血型 ML）绵羊的血液免疫高钾型（HK）（血型 MM）绵羊制备的抗-L 血清含有一种抗体，该抗体可刺激低钾型（LK）（LL 型）绵羊红细胞中的钾泵内流增加四到六倍。在长期的体外孵育实验中，用抗-L 敏化的 LK 绵羊红细胞在 37°C 孵育两天后表现出钾净增加，而 HK-非免疫（NI）-血清处理的对照细胞失去钾。该抗体可被 LK（LL）绵羊红细胞吸收，但不能被 HK 绵羊红细胞吸收。动力学实验表明，产生泵的半最大刺激的外部钾浓度（[K+]0）（[Na+]0=0，用 Mg++取代）在抗-L 血清处理或未处理的 LK 细胞中是相同的（0.25 mM）。用对氯汞苯磺酸（PCMBS）法制备具有不同 [K+]i（Na+ 替代）的 LK 细胞。在 [K+]0=5 mM 时，随着 [K+]i 从 1 增加到 70 mM，泵内流在抗-L 血清处理的 LK 细胞中减少，而用 HK-NI-血清处理的 LK 细胞在 [K+]i=35 mM 时停止泵。抗-L 血清的暴露使 LK 细胞的泵位数量增加近两倍，这可以通过 LK 绵羊红细胞结合放射性标记哇巴因来测量。这些发现表明，L 抗原与其抗体形成复合物可通过改变泵的动力学和增加泵位数量来刺激 LK 绵羊红细胞中的主动转运。
