Muscle tension recording was used to study adrenergic contractile reactions of pulmonary artery smooth muscles in rabbits. Stimulation of α-adrenoceptors induced contraction of pulmonary artery smooth muscle cells. Endothelium partially inhibited the contractile effect of α-adrenoceptor agonists. Activation of smooth muscle β-adrenoceptors in pulmonary arteries produced a dual dose-dependent effect (relaxation at agonist concentrations of 10 nM-1 μM and contraction at concentrations above 10 μM). The contractile effect of β-adrenoceptor activation in smooth muscle cells is a specific feature of pulmonary arteries probably related to peculiarities of cAMP-signaling in these cells.
- Pulmonary arteries
- Smooth muscles
ASJC Scopus subject areas
- Biochemistry, Genetics and Molecular Biology(all)