Dataset Information

Role of the bradykinin B2 receptor in a rat model of local heart irradiation.

ABSTRACT:

Purpose

Radiation-induced heart disease (RIHD) is a delayed effect of radiotherapy for cancers of the chest, such as breast, esophageal, and lung. Kinins are small peptides with cardioprotective properties. We previously used a rat model that lacks the precursor kininogen to demonstrate that kinins are involved in RIHD. Here, we examined the role of the kinin B2 receptor (B2R) in early radiation-induced signaling in the heart.

Materials and methods

Male Brown Norway rats received the B2R-selective antagonist HOE-140 (icatibant) via osmotic minipump from 5 days before until 4 weeks after 21 Gy local heart irradiation. At 4 weeks, signaling events were measured in left ventricular homogenates and nuclear extracts using western blotting and real-time polymerase chain reaction. Numbers of CD68-positive (monocytes/macrophages), CD2-positive (T-lymphocytes), and mast cells were measured using immunohistochemistry.

Results

Radiation-induced c-Jun phosphorylation and nuclear translocation were enhanced by HOE-140. HOE-140 did not modify endothelial nitric oxide synthase (eNOS) phosphorylation or alter numbers of CD2-positive or mast cells, but enhanced CD68-positive cell counts in irradiated hearts.

Conclusions

B2R signaling may regulate monocyte/macrophage infiltration and c-Jun signals in the irradiated heart. Although eNOS is a main target for kinins, the B2R may not regulate eNOS phosphorylation in response to radiation.

SUBMITTER: Lieblong BJ

PROVIDER: S-EPMC4743985 | biostudies-literature | 2015 Aug

REPOSITORIES: biostudies-literature

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Role of the bradykinin B2 receptor in a rat model of local heart irradiation.

Lieblong Benjamin J BJ Sridharan Vijayalakshmi V Srivastava Anup K AK Moros Eduardo G EG Sharma Sunil K SK Boerma Marjan M

International journal of radiation biology 20150619 8

<h4>Purpose</h4>Radiation-induced heart disease (RIHD) is a delayed effect of radiotherapy for cancers of the chest, such as breast, esophageal, and lung. Kinins are small peptides with cardioprotective properties. We previously used a rat model that lacks the precursor kininogen to demonstrate that kinins are involved in RIHD. Here, we examined the role of the kinin B2 receptor (B2R) in early radiation-induced signaling in the heart.<h4>Materials and methods</h4>Male Brown Norway rats received ...[more]

PMID: 25955317

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Dataset Information

Role of the bradykinin B2 receptor in a rat model of local heart irradiation.

Purpose

Materials and methods

Results

Conclusions

Publications

Role of the bradykinin B2 receptor in a rat model of local heart irradiation.

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