Multiple ryanodine receptor subtypes and heterogeneous ryanodine receptor-gated Ca2+ stores in pulmonary arterial smooth muscle cells
- PMID: 15863441
- DOI: 10.1152/ajplung.00328.2004
Multiple ryanodine receptor subtypes and heterogeneous ryanodine receptor-gated Ca2+ stores in pulmonary arterial smooth muscle cells
Abstract
Ryanodine receptors (RyRs) of pulmonary arterial smooth muscle cells (PASMCs) play important roles in major physiological processes such as hypoxic pulmonary vasoconstriction and perinatal pulmonary vasodilatation. Recent studies show that three subtypes of RyRs are coexpressed and RyR-gated Ca2+ stores are distributed heterogeneously in systemic vascular myocytes. However, the molecular identity and subcellular distribution of RyRs have not been examined in PASMCs. In this study we detected mRNA and proteins of all three subtypes in rat intralobar PASMCs using RT-PCR and Western blot. Quantitative real-time RT-PCR showed that RyR2 mRNA was most abundant, approximately 15-20 times more than the other two subtypes. Confocal fluorescence microscopy revealed that RyRs labeled with BODIPY TR-X ryanodine were localized in the peripheral and perinuclear regions and were colocalized with sarcoplasmic reticulum labeled with Fluo-5N. Immunostaining showed that the subsarcolemmal regions exhibited clear signals of RyR1 and RyR2, whereas the perinuclear compartments contained mainly RyR1 and RyR3. Ca2+ sparks were recorded in both regions, and their activities were enhanced by a subthreshold concentration of caffeine or by endothelin-1, indicating functional RyR-gated Ca2+ stores. Moreover, 18% of the perinuclear sparks were prolonged [full duration/half-maximum (FDHM) = 193.3 +/- 22.6 ms] with noninactivating kinetics, in sharp contrast to the typical fast inactivating Ca2+ sparks (FDHM = 44.6 +/- 3.2 ms) recorded in the same PASMCs. In conclusion, multiple RyR subtypes are expressed differentially in peripheral and perinuclear RyR-gated Ca2+ stores; the molecular complexity and spatial heterogeneity of RyRs may facilitate specific Ca2+ regulation of cellular functions in PASMCs.
Similar articles
-
Type-3 ryanodine receptors mediate hypoxia-, but not neurotransmitter-induced calcium release and contraction in pulmonary artery smooth muscle cells.J Gen Physiol. 2005 Apr;125(4):427-40. doi: 10.1085/jgp.200409232. J Gen Physiol. 2005. PMID: 15795312 Free PMC article.
-
Conformation of ryanodine receptor-2 gates store-operated calcium entry in rat pulmonary arterial myocytes.Cardiovasc Res. 2016 Jul 1;111(1):94-104. doi: 10.1093/cvr/cvw067. Epub 2016 Mar 24. Cardiovasc Res. 2016. PMID: 27013634 Free PMC article.
-
Stretch-induced Ca2+ signalling in vascular smooth muscle cells depends on Ca2+ store segregation.Cardiovasc Res. 2014 Jul 15;103(2):313-23. doi: 10.1093/cvr/cvu069. Epub 2014 Apr 1. Cardiovasc Res. 2014. PMID: 24692174
-
Role of ryanodine receptor subtypes in initiation and formation of calcium sparks in arterial smooth muscle: comparison with striated muscle.J Biomed Biotechnol. 2009;2009:135249. doi: 10.1155/2009/135249. Epub 2009 Dec 8. J Biomed Biotechnol. 2009. PMID: 20029633 Free PMC article. Review.
-
Ca2+ stores regulate ryanodine receptor Ca2+ release channels via luminal and cytosolic Ca2+ sites.Clin Exp Pharmacol Physiol. 2007 Sep;34(9):889-96. doi: 10.1111/j.1440-1681.2007.04708.x. Clin Exp Pharmacol Physiol. 2007. PMID: 17645636 Review.
Cited by
-
Rieske iron-sulfur protein induces FKBP12.6/RyR2 complex remodeling and subsequent pulmonary hypertension through NF-κB/cyclin D1 pathway.Nat Commun. 2020 Jul 15;11(1):3527. doi: 10.1038/s41467-020-17314-1. Nat Commun. 2020. PMID: 32669538 Free PMC article.
-
Calcium-Dependent Ion Channels and the Regulation of Arteriolar Myogenic Tone.Front Physiol. 2021 Nov 8;12:770450. doi: 10.3389/fphys.2021.770450. eCollection 2021. Front Physiol. 2021. PMID: 34819877 Free PMC article. Review.
-
Cytoplasmic nanojunctions between lysosomes and sarcoplasmic reticulum are required for specific calcium signaling.F1000Res. 2014 Apr 22;3:93. doi: 10.12688/f1000research.3720.1. eCollection 2014. F1000Res. 2014. PMID: 25126414 Free PMC article.
-
Function and expression of ryanodine receptors and inositol 1,4,5-trisphosphate receptors in smooth muscle cells of murine feed arteries and arterioles.J Physiol. 2012 Apr 15;590(8):1849-69. doi: 10.1113/jphysiol.2011.222083. Epub 2012 Feb 13. J Physiol. 2012. PMID: 22331418 Free PMC article.
-
Dynamics of a three-variable nonlinear model of vasomotion: comparison of theory and experiment.Biophys J. 2007 Sep 1;93(5):1534-56. doi: 10.1529/biophysj.107.106278. Epub 2007 May 4. Biophys J. 2007. PMID: 17483163 Free PMC article.
Publication types
MeSH terms
Substances
Grants and funding
LinkOut - more resources
Full Text Sources
Miscellaneous