Quaternary ammonium sulfanilamide: a membrane-impermeant carbonic anhydrase inhibitor.
Quaternary ammonium sulfanilamide: a membrane-impermeant carbonic anhydrase inhibitor.
复制标题
季铵磺胺：一种非膜渗透性碳酸酐酶抑制剂。
DOI：
10.1152/ajpregu.1987.252.5.r959
复制
发表时间：
1987
期刊：
影响因子：
--
通讯作者：
R. Henry
中科院分区：
文献类型：
--
作者：
R. Henry
测试了一种新型碳酸酐酶（CA）抑制剂季铵磺胺（QAS）作为CA抑制剂的效力及其被排除在生物膜之外的能力。QAS与纯牛CA II和来自青蟹Callinectes sapidus鳃的CA的抑制剂滴定图产生约15 μ M的Ki值;因此QAS是相对弱但有效的CA抑制剂。通过两种独立的方法直接检测QAS的渗透性。如使用18 O标记的质谱仪CA测定法对完整细胞测定的，在5 mM QAS中孵育24 h的人红细胞中排除了抑制剂。将QAS注入C. sapidus（1或10 mM）不穿过鳃的基底膜。注射后96 h，该化合物从血淋巴中清除，在此期间的任何时间都不能在鳃组织匀浆中检测到QAS。总鳃CA活性仅略有减少后，QAS注射。这些数据表明，QAS是一种CA抑制剂，生物膜是不可渗透的，可以在体内或体外用于膜相关CA的研究。
A novel carbonic anhydrase (CA) inhibitor, quaternary ammonium sulfanilamide (QAS), was tested for potency as a CA inhibitor and for its ability to be excluded from permeating biological membranes. Inhibitor titration plots of QAS vs. pure bovine CA II and CA from the gills of the blue crab, Callinectes sapidus, yielded Ki values of approximately 15 microM; thus QAS is a relatively weak but effective CA inhibitor. Permeability of the QAS was directly tested by two independent methods. The inhibitor was excluded from human erythrocytes incubated in 5 mM QAS for 24 h as determined using an 18O-labeled mass spectrometer CA assay for intact cells. Also QAS injected into the hemolymph of C. sapidus (1 or 10 mM) did not cross the basal membrane of the gill. The compound was cleared from the hemolymph by 96 h after injection, and at no time during that period could the QAS be detected in homogenates of gill tissue. Total branchial CA activity was only slightly reduced following the QAS injection. These data indicate that QAS is a CA inhibitor to which biological membranes are impermeable and that can be used in vivo or in vitro in the study of membrane-associated CA.