Dataset Information

Glucagon-like peptide-1 receptor expression after myocardial infarction: Imaging study using ⁶⁸Ga-NODAGA-exendin-4 positron emission tomography.

ABSTRACT:

Background

Activation of glucagon-like peptide-1 receptor (GLP-1R) signaling protects against cardiac dysfunction and remodeling after myocardial infarction (MI). The aim of the study was to evaluate ⁶⁸Ga-NODAGA-exendin-4 positron emission tomography (PET) for assessment of GLP-1R expression after MI in rats.

Methods and results

Rats were studied at 3 days, 1 and 12 weeks after permanent coronary ligation or a sham-operation. Rats were injected with ⁶⁸Ga-NODAGA-exendin-4 and scanned with PET and contrast-enhanced computed tomography (CT) followed by digital autoradiography and histology of left ventricle tissue sections. ⁶⁸Ga-NODAGA-exendin-4 PET/CT showed focally increased tracer uptake in the infarcted regions peaking at 3 days and continuing at 1 week after MI. Pre-treatment with an unlabeled exendin-4 peptide significantly reduced ⁶⁸Ga-NODAGA-exendin-4 uptake. By autoradiography, ⁶⁸Ga-NODAGA-exendin-4 uptake was 8.6-fold higher in the infarcted region and slightly increased also in the remote, non-infarcted myocardium at 1 week and 12 weeks post-MI compared with sham. Uptake of ⁶⁸Ga-NODAGA-exendin-4 correlated with the amount of CD68-positive macrophages in the infarcted area and alpha-smooth muscle actin staining in the remote myocardium.

Conclusions

⁶⁸Ga-NODAGA-exendin-4 PET detects up-regulation of cardiac GLP-1R expression during healing of MI in rats and may provide information on the activated repair mechanisms after ischemic myocardial injury.

SUBMITTER: Stahle M

PROVIDER: S-EPMC7749060 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature

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Publications

Glucagon-like peptide-1 receptor expression after myocardial infarction: Imaging study using <sup>68</sup>Ga-NODAGA-exendin-4 positron emission tomography.

Ståhle Mia M Kytö Ville V Kiugel Max M Liljenbäck Heidi H Metsälä Olli O Käkelä Meeri M Li Xiang-Guo XG Oikonen Vesa V Saukko Pekka P Nuutila Pirjo P Knuuti Juhani J Roivainen Anne A Saraste Antti A

Journal of nuclear cardiology : official publication of the American Society of Nuclear Cardiology 20181213 6

<h4>Background</h4>Activation of glucagon-like peptide-1 receptor (GLP-1R) signaling protects against cardiac dysfunction and remodeling after myocardial infarction (MI). The aim of the study was to evaluate <sup>68</sup>Ga-NODAGA-exendin-4 positron emission tomography (PET) for assessment of GLP-1R expression after MI in rats.<h4>Methods and results</h4>Rats were studied at 3 days, 1 and 12 weeks after permanent coronary ligation or a sham-operation. Rats were injected with <sup>68</sup>Ga-NODA ...[more]

PMID: 30547299

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