Tinker J P, Coulson R, Weiner I M
J Pharmacol Exp Ther. 1981 Sep;218(3):600-7.
High molecular weight inhibitors of carbonic anhydrase were synthesized and tested in isolated perfused rat kidneys. One such inhibitor, dextran-bound inhibitor (DBI), had a mean molecular mass of 6700 daltons. Its renal clearance was equal to the clearance of inulin and its intrarenal volume of distribution was close to that of inulin. The maximal effect of DBI on bicarbonate excretion was the same as that of acetazolamide. This action could not be attributed to breakdown products of DBI. DBI does not enter erythrocytes. Another inhibitor, extra-large inhibitor, had a mean molecular mass of 99,000 daltons. It was scarcely filterable. It did not increase bicarbonate excretion when added to perfusates in concentrations greater than effective concentrations of DBI. It is concluded that activity of carbonic anhydrase bound to luminal membranes of renal cells is critical for normal reabsorption of bicarbonate.
合成了高分子量碳酸酐酶抑制剂，并在离体灌注大鼠肾脏中进行了测试。其中一种抑制剂，葡聚糖结合抑制剂（DBI），平均分子量为6700道尔顿。其肾清除率与菊粉清除率相等，肾内分布容积与菊粉相近。DBI对碳酸氢盐排泄的最大作用与乙酰唑胺相同。这种作用不能归因于DBI的分解产物。DBI不进入红细胞。另一种抑制剂，超大抑制剂，平均分子量为99000道尔顿。它几乎不能被滤过。当以高于DBI有效浓度的浓度添加到灌注液中时，它不会增加碳酸氢盐的排泄。结论是，与肾细胞管腔膜结合的碳酸酐酶活性对于碳酸氢盐的正常重吸收至关重要。
