ABSTRACT

Introduction: In acute lung injury induced by oleic acid there is an increase in the production of ET-1, but has not reported the distribution of their receptors in the pulmonary arteries.
Objective: To determine the immunohistochemical expression of ET-1 ET_A and ET_B and its distribution in the pulmonary arteries of dogs with acute lung injury induced by oleic acid.
Material and methods: There were 12 dogs were divided into two study groups: Group I (n = 6): healthy control; Group II (n = 6): acute lung injury produced with AO DPA. Was evaluated immunohistochemically the presence of ET-1, ET_A and ET_B in the proximal and distal segments of the pulmonary arteries of both groups.
Results: In both groups found expression of ET-1 primarily in endothelial and smooth muscle, the location of the ET_A was in the middle layer of the proximal segments of the pulmonary arteries, in normal animals and in those who developed DPA; the B receptors were expressed in the media and intima, the middle layer observed in the distal region of the artery, while the intima is expressed in the proximal part of it.
Conclusion: The immunohistochemical expression of ET-1 in healthy dogs as oleic acid-induced DPA is shown in endothelial and smooth muscle, while ET_A receptors were observed in the middle layer of the pulmonary arteries in their proximal portion, unlike the ET_B expressed in the middle layer of the distal portion, while the staining in the intima is more abundant in the proximal segments.

KEYWORDS

Endothelin, ET_A receptors, ET_B receptors, acute lung injury.

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