Abstract
Pulmonary arterial hypertension (PAH) is a chronic condition characterized by vascular remodeling and increased vaso-reactivity. PAH is more common in females than in males (~3:1). Connexin (Cx)43 has been shown to be involved in cellular communication within the pulmonary vasculature. Therefore, we investigated the role of Cx43 in pulmonary vascular reactivity using Cx43 heterozygous (Cx43+/-) mice and 37,43Gap27, which is a pharmacological inhibitor of Cx37 and Cx43. Contraction and relaxation responses were studied in intra-lobar pulmonary arteries (IPAs) derived from normoxic mice and hypoxic mice using wire myography. IPAs from male Cx43+/- mice displayed a small but significant increase in the contractile response to endothelin-1 (but not 5-hydroxytryptamine) under both normoxic and hypoxic conditions. There was no difference in the contractile response to endothelin-1 (ET-1) or 5-hydroxytryptamine (5-HT) in IPAs derived from female Cx43+/-mice compared to wildtype mice. Relaxation responses to methacholine (MCh) were attenuated in IPAs from male and female Cx43+/- mice or by pre-incubation of IPAs with 37,43Gap27. Nω-Nitro-L-arginine methyl ester (l-NAME) fully inhibited MCh-induced relaxation. In conclusion, Cx43 is involved in nitric oxide (NO)-induced pulmonary vascular relaxation and plays a gender-specific and agonist-specific role in pulmonary vascular contractility. Therefore, reduced Cx43 signaling may contribute to pulmonary vascular dysfunction.
Original language | English |
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Journal | International Journal of Molecular Sciences |
Volume | 19 |
Issue number | 7 |
Early online date | 27 Jun 2018 |
DOIs | |
Publication status | Published - Jul 2018 |
Keywords
- connexin43 (Cx43)
- pulmonary arterial hypertension (PAH)
- gap junction
- vascular reactivity
- nitric oxide
- serotonin
- endothelin-1
- isoprenaline
ASJC Scopus subject areas
- Molecular Biology
- Spectroscopy
- Catalysis
- Inorganic Chemistry
- Computer Science Applications
- Physical and Theoretical Chemistry
- Organic Chemistry