Send to

Choose Destination
Cell Physiol Biochem. 2013;32(1):11-24. doi: 10.1159/000350119. Epub 2013 Jul 4.

Investigation of the inhibitory effects of the benzodiazepine derivative, 5-BDBD on P2X4 purinergic receptors by two complementary methods.

Author information

Institute of Human Physiology and Clinical Experimental Research, Semmelweis University, Budapest, Hungary.



ATP-gated P2X4 purinergic receptors (P2X4Rs) are cation channels with important roles in diverse cell types. To date, lack of specific inhibitors has hampered investigations on P2X4Rs. Recently, the benzodiazepine derivative, 5-BDBD has been proposed to selectively inhibit P2X4Rs. However, limited evidences are currently available on its inhibitory properties. Thus, we aimed to characterize the inhibitory effects of 5-BDBD on recombinant human P2X4Rs.


We investigated ATP-induced intracellular Ca(2+) signals and whole cell ion currents in HEK 293 cells that were either transiently or stably transfected with hP2X4Rs.


Our data show that ATP (< 1 μM) stimulates P2X4R-mediated Ca(2+) influx while endogenously expressed P2Y receptors are not activated to any significant extent. Both 5-BDBD and TNP-ATP inhibit ATP-induced Ca(2+) signals and inward ion currents in a concentration-dependent manner. Application of two different concentrations of 5-BDBD causes a rightward shift in ATP dose-response curve. Since the magnitude of maximal stimulation does not change, these data suggest that 5-BDBD may competitively inhibit the P2X4Rs.


Our results demonstrate that application of submicromolar ATP concentrations allows reliable assessment of recombinant P2XR functions in HEK 293 cells. Furthermore, 5-BDBD and TNP-ATP have similar inhibitory potencies on the P2X4Rs although their mechanisms of actions are different.

[Indexed for MEDLINE]
Free full text

Supplemental Content

Full text links

Icon for S. Karger AG, Basel, Switzerland
Loading ...
Support Center