Dataset Information

Detecting Validated Intracellular ROS Generation with ¹⁸F-dihydroethidine-Based PET.

ABSTRACT:

Purpose

To determine the sensitivity of the ¹⁸F-radiolabelled dihydroethidine analogue ([¹⁸F]DHE) to ROS in a validated ex vivo model of tissue oxidative stress.

Procedures

The sensitivity of [¹⁸F]DHE to various ROS-generating systems was first established in vitro. Then, isolated rat hearts were perfused under constant flow, with contractile function monitored by intraventricular balloon. Cardiac uptake of infused [¹⁸F]DHE (50-150 kBq.min^-1) was monitored by γ-detection, while ROS generation was invoked by menadione infusion (0, 10, or 50 μm), validated by parallel measures of cardiac oxidative stress.

Results

[¹⁸F]DHE was most sensitive to oxidation by superoxide and hydroxyl radicals. Normalised [¹⁸F]DHE uptake was significantly greater in menadione-treated hearts (1.44 ± 0.27) versus control (0.81 ± 0.07) (p < 0.05, n = 4/group), associated with concomitant cardiac contractile dysfunction, glutathione depletion, and PKG1α dimerisation.

Conclusion

[¹⁸F]DHE reports on ROS in a validated model of oxidative stress where perfusion (and tracer delivery) is unlikely to impact its pharmacokinetics.

SUBMITTER: Waters ECT

PROVIDER: S-EPMC9085669 | biostudies-literature | 2022 Jun

REPOSITORIES: biostudies-literature

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Publications

Detecting Validated Intracellular ROS Generation with <sup>18</sup>F-dihydroethidine-Based PET.

Waters Edward C T ECT Baark Friedrich F Yu Zilin Z Mota Filipa F Eykyn Thomas R TR Yan Ran R Southworth Richard R

Molecular imaging and biology 20211124 3

<h4>Purpose</h4>To determine the sensitivity of the <sup>18</sup>F-radiolabelled dihydroethidine analogue ([<sup>18</sup>F]DHE) to ROS in a validated ex vivo model of tissue oxidative stress.<h4>Procedures</h4>The sensitivity of [<sup>18</sup>F]DHE to various ROS-generating systems was first established in vitro. Then, isolated rat hearts were perfused under constant flow, with contractile function monitored by intraventricular balloon. Cardiac uptake of infused [<sup>18</sup>F]DHE (50-150 kBq.m ...[more]

PMID: 34820762

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Dataset Information

Detecting Validated Intracellular ROS Generation with ¹⁸F-dihydroethidine-Based PET.

Purpose

Procedures

Results

Conclusion

Publications

Detecting Validated Intracellular ROS Generation with <sup>18</sup>F-dihydroethidine-Based PET.

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Dataset Information

Detecting Validated Intracellular ROS Generation with 18F-dihydroethidine-Based PET.

Purpose

Procedures

Results

Conclusion

Publications

Detecting Validated Intracellular ROS Generation with <sup>18</sup>F-dihydroethidine-Based PET.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

Detecting Validated Intracellular ROS Generation with ¹⁸F-dihydroethidine-Based PET.