Requirement of Pretone by Thromboxane A2 for Hypoxic Pulmonary Vasoconstriction in Precision-cut Lung Slices of Rat.
10.4196/kjpp.2012.16.1.59
- Author:
Su Jung PARK
1
;
Hae Young YOO
;
Hye Jin KIM
;
Jin Kyoung KIM
;
Yin Hua ZHANG
;
Sung Joon KIM
Author Information
1. Department of Physiology, Seoul National University College of Medicine, Seoul 110-799, Korea. sjoonkim@snu.ac.kr
- Publication Type:Original Article
- Keywords:
Lung slice;
Hypoxic pulmonary vasoconstriction;
Thromboxane A2;
Airway smooth muscle
- MeSH:
15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic Acid;
Animals;
Bronchioles;
Constriction;
Contracts;
Lung;
Perfusion;
Pulmonary Artery;
Rats;
Relaxation;
Thromboplastin;
Thromboxane A2;
Vasoconstriction;
Ventilation
- From:The Korean Journal of Physiology and Pharmacology
2012;16(1):59-64
- CountryRepublic of Korea
- Language:English
-
Abstract:
Hypoxic pulmonary vasoconstriction (HPV) is physiologically important response for preventing mismatching between ventilation and perfusion in lungs. The HPV of isolated pulmonary arteries (HPV-PA) usually require a partial pretone by thromboxane agonist (U46619). Because the HPV of ventilated/perfused lungs (HPV-lung) can be triggered without pretone conditioning, we suspected that a putative tissue factor might be responsible for the pretone of HPV. Here we investigated whether HPV can be also observed in precision-cut lung slices (PCLS) from rats. The HPV in PCLS also required partial contraction by U46619. In addition, K+ channel blockers (4AP and TEA) required U46619-pretone to induce significant contraction of PA in PCLS. In contrast, the airways in PCLS showed reversible contraction in response to the K+ channel blockers without pretone conditioning. Also, the airways showed no hypoxic constriction but a relaxation under the partial pretone by U46619. The airways in PCLS showed reliable, concentration-dependent contraction by metacholine (EC50, ~210 nM). In summary, the HPV in PCLS is more similar to isolated PA than V/P lungs. The metacholine-induced constriction of bronchioles suggested that the PLCS might be also useful for studying airway physiology in situ.
