Inoue A, Tominaga Y, Nishio H, Segawa T, Nakata Y
Department of Pharmacology, Hiroshima University School of Medicine, Japan.
Neurochem Int. 1993 Jun;22(6):547-53. doi: 10.1016/0197-0186(93)90029-5.
In the absence of detergent, specific binding of [3H]GR65630, a 5-hydroxytryptamine3 (5-HT3) antagonist, determined in the presence of 5-HT3 receptor antagonist ICS205-930, was at most 30% of the total binding. To decrease the level of nonspecific binding, the effects of detergents on [3H]GR65630 binding to rat cortical membranes were investigated. The use of a detergent (0.1% Lubrol PX or Triton X-100) decreased nonspecific binding, increasing the proportion of specific binding to 70% of total binding. In the presence of 0.1% Triton X-100, binding of [3H]GR65630 was rapid, reversible and saturable at 25 degrees C. The rank order of 5-HT3 receptor active drugs in inhibiting [3H]GR65630 binding was quipazine > ICS205-930 > 2-methyl-5-HT = 5-HT > metoclopramide, which confirmed that [3H]GR65630 efficiently labeled 5-HT3 receptors in the presence of Triton X-100. Triton X-100 improved 5-HT3 receptor binding with rat brain membranes.
在没有去污剂的情况下,在5-羟色胺3(5-HT3)受体拮抗剂ICS205-930存在下测定的[3H]GR65630(一种5-HT3拮抗剂)的特异性结合最多占总结合的30%。为了降低非特异性结合水平,研究了去污剂对[3H]GR65630与大鼠皮质膜结合的影响。使用去污剂(0.1%月桂醇聚醚硫酸酯钠或 Triton X-100)可降低非特异性结合,使特异性结合比例增加至总结合的70%。在0.1% Triton X-100存在下,[3H]GR65630的结合在25℃时快速、可逆且可饱和。5-HT3受体活性药物在抑制[3H]GR65630结合方面的排序为:喹哌嗪 > ICS205-930 > 2-甲基-5-羟色胺 = 5-羟色胺 > 甲氧氯普胺,这证实了在Triton X-100存在下[3H]GR65630能有效标记5-HT3受体。Triton X-100改善了[3H]GR65630与大鼠脑膜的结合。