Table 1.

Effect of ABC transport inhibitors on cyclic nucleotide transport

Compound typeCompoundConcentration (μmol l–1)cGMP transport ratio (% of control)cAMP transport ratio (% of control)
Broad-specificity ABC transporter inhibitorGlibenclamide5011±2***1±7***
1036±3***23±9***
164±7*94±19
ABCG2 substratesMethotrexate400053±8*41±5*
50071±12
10084±2791±8
50114±1591±18
Mitoxantrone2027±7**
263±10
0.275±17
ABCC substratesDipyridamole1095±26
186±9
0.179±13
  • cGMP and/or cAMP transport assays were performed on wild-type tubules in the absence (controls, 100%) or presence of compounds known to affect specific transporter families

    Values are mean ± s.e.m. (N⩾5). Statistical significance was verified by Student's t-test compared with control (no added drugs), taking P<0.05 as the critical level. *P<0.05, **P<0.01, ***P<0.001