The contractile response of isolated small pulmonary arteries induced by activated macrophages

Title:

The contractile response of isolated small pulmonary arteries induced by activated macrophages

Creator:

Žaloudíková, M., Jan Herget, and Martin Vízek

Identifier:

https://cdk.lib.cas.cz/client/handle/uuid:8243765b-94cd-4f15-983c-02f7649947b4
uuid:8243765b-94cd-4f15-983c-02f7649947b4

Subject:

Fyziologie člověka a srovnávací fyziologie, tepny, kyslík, arteries, oxygen, isolated pulmonary arteries, reactive oxygen species, macrophage, 14, and 612

Type:

article, články, model:article, and TEXT

Format:

print

Description:

To test whether macrophages can play any role in hypoxic pulmonary vasoconstriction, we tested the in vitro response of rings from small pulmonary arteries to the activation of macrophages by FMLP, a substance stimulating predominantly membrane-bound NADPH oxidase. A small vessel myograph was used to measure the responses of rings from small pulmonary arteries (300-400 μ m) isolated from rat lungs. Rings from 5 rats were placed into both chambers of the myograph. The vessels were stabilized for 40 min and then normalized by automatic stretching to a wall tension equivalent to the intravascular pressure 30 mm Hg. At the start of each experiment, vessels were exposed to 80 mM K + to obtain maximal contractile response, which was used to normalize subsequent contractile responses. 2x10 6 viable macrophages, obtained by peritoneal lavage, were added into one chamber, then 5 μ M FMLP was administrated to both chambers and the tension measurement was started. The hydrogen peroxide concentration produced by stimulated macrophages was measured luminometrically. The concentrations of H 2 O 2 in specimens from chambers containing activated macrophages rose from 3.5±1.5 nM to 110±28 nM within 25 min of stimulation, while FMLP itself didn’t increase the H 2 O 2 concentration from the baseline value (4.5±3 nM) in samples from control chambers. After FMLP administration, the tension of the vessel rings in the presence of macrophages reached 0.23±0.07 of maximal contractile response, it did not change in controls. The additi on of ROS scavenger 4-hydroxy- TEMPO blocked the contractile response to the activation of macrophages. We conclude that the activation of macrophages stimulates the contraction of small pulmonary arteries and that this contraction is probably mediated by reactive oxygen species., M. Žaloudíková, J. Herget, M. Vízek., and Obsahuje bibliografii a bibliografické odkazy

Language:

English

Rights:

http://creativecommons.org/licenses/by-nc-sa/4.0/
policy:public

Source:

Physiological research | 2014 Volume:63 | Number:2

Harvested from:

CDK

Metadata only:

false