Jonathan H. Jaggar, Ph.D.
Maury Bronstein Professor
Department of Physiology
The University of Tennessee Health Science Center
894 Union Avenue
Memphis, TN 38163
Phone: (901) 448-1208
Office: 402 Nash Research Building
Email: Jonathan H. Jaggar
- Ph.D. Institution: University of Sheffield, United Kingdom
Arterial diameter, a primary determinant of systemic blood pressure, is regulated by the contractile state of smooth muscle cells in the arterial wall. One critical regulator of smooth muscle contractility is the intracellular calcium ion concentration. Smooth muscle cells control intracellular calcium concentration by regulating cellular influx, release, sequestration and extrusion. Since membrane potential regulates calcium entry in smooth muscle cells, ion channels that modulate membrane potential also change cellular contractility. Recent studies have discovered that local and global elevations in cytosolic calcium occur in smooth muscle cells. These different calcium signaling events not only regulate contractility, but may also regulate a number of other physiological functions. We are currently investigating sarcolemma ion channels that control membrane potential and calcium entry in arterial smooth muscle cells and the properties, physiological targets, and regulation of arterial diameter by different intracellullar calcium signals. Research in the laboratory involves a multi-faceted approach, studying events at molecular, cellular and intact artery levels. Techniques include patch clamp electrophysiology, rapid confocal calcium imaging, conventional calcium imaging, diameter measurement of pressurized arteries, and molecular biology.
- Nnorom CC, Davis C, Fedinec AL, Howell K, Jaggar JH, Parfenova H, Pourcyrous M, Leffler CW. Contributions of KATP and KCa channels to cerebral arteriolar dilation to hypercapnia in neonatal brain. Physiol Rep. 2014 Aug 28;2(8). pii: e12127. doi: 10.14814/phy2.12127. Print 2014 Aug 1. PubMed PMID: 25168876.
- Nourian Z, Li M, Leo MD, Jaggar JH, Braun AP, Hill MA. Large conductance Ca2+-activated K+ channel (BKCa) Î±-subunit splice variants in resistance arteries from rat cerebral and skeletal muscle vasculature. PLoS One. 2014 Jun 12;9(6):e98863. doi: 10.1371/journal.pone.0098863. eCollection 2014. PubMed PMID: 24921651; PubMed Central PMCID: PMC4055454.
- Peixoto-Neves D, Leal-Cardoso JH, Jaggar JH. Eugenol dilates rat cerebral arteries by inhibiting smooth muscle cell voltage-dependent calcium channels. J Cardiovasc Pharmacol. 2014 Jun 11. [Epub ahead of print] PubMed PMID: 24921632.
- Evanson KW, Bannister JP, Leo MD, Jaggar JH. LRRC26 is a functional BK channel auxiliary Î³ subunit in arterial smooth muscle cells. Circ Res. 2014 Aug 1;115(4):423-31. doi: 10.1161/CIRCRESAHA.115.303407. Epub 2014 Jun 6. PubMed PMID: 24906643; PubMed Central PMCID: PMC4119551.
- Ye Y, Jian K, Jaggar JH, Bukiya AN, Dopico AM. Type 2 ryanodine receptors are highly sensitive to alcohol. FEBS Lett. 2014 May 2;588(9):1659-65. doi: 10.1016/j.febslet.2014.03.005. Epub 2014 Mar 12. PubMed PMID: 24631538; PubMed Central PMCID: PMC4193545.
- Leo MD, Bannister JP, Narayanan D, Nair A, Grubbs JE, Gabrick KS, Boop FA, Jaggar JH. Dynamic regulation of Î²1 subunit trafficking controls vascular contractility. Proc Natl Acad Sci U S A. 2014 Feb 11;111(6):2361-6. doi: 10.1073/pnas.1317527111. Epub 2014 Jan 24. PubMed PMID: 24464482; PubMed Central PMCID: PMC3926029.