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(Fig. 1—the PI-positive cell number in the simulated
ischaemia treatment group was normalised to 100%).
When cells were incubated in the simulated ischaemia
conditions in the presence of N6-cyclopentyladenosine
(CPA, 10 nM), the number of PI-positive cells was re-
duced by 86.18 6.19%, to a level similar to that seen
in cells exposed to normal oxygenated media (control).
The series of adenosine receptor agonists tested in this
assay all demonstrated cardioprotective properties at
the same concentration (10 nM). Compound 2e (84.84
3.0% reduction in dead cell number) demonstrated sim-
ilar efficacy to CPA at this concentration, whilst com-
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thine (DPCPX), over the range of agonist concentra-
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These data indicate that the adenosine receptor
analogues evaluated have significant cardioprotective
effects at low nanomolar concentrations. The protective
effects of the analogues were reduced but not abolished
in the presence of the A1AR antagonist DPCPX, raising
the possibility that there was some benefit derived from
the antioxidant attachments. We are currently investigat-
ing this potential cardioprotective mechanism further.
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Acknowledgment
16. Das, S.; Powell, S. R.; Wang, P.; Divald, A.; Nesaretnam,
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The authors thank the ARC Centre of Excellence for
Free Radical Chemistry and Biotechnology for financial
support.
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Supplementary data
Supplementary data associated with this article can be
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