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.
- Kidd MW, Leo MD, Bannister JP, Jaggar JH. Intravascular pressure enhances the abundance of functional Kv1.5 channels at the surface of arterial smooth muscle cells. Sci Signal. 2015 Aug 18;8(390):ra83. doi: 10.1126/scisignal.aac5128. PubMed PMID: 26286025.
- Leo MD, Bulley S, Bannister JP, Kuruvilla KP, Narayanan D, Jaggar JH. Angiotensin II stimulates internalization and degradation of arterial myocyte plasma membrane BK channels to induce vasoconstriction. Am J Physiol Cell Physiol. 2015 Sep 15;309(6):C392-402. doi: 10.1152/ajpcell.00127.2015. Epub 2015 Jul 15. PubMed PMID: 26179602; PubMed Central PMCID: PMC4572372.
- Peixoto-Neves D, Wang Q, Leal-Cardoso JH, Rossoni LV, Jaggar JH. Eugenol dilates mesenteric arteries and reduces systemic BP by activating endothelial cell TRPV4 channels. Br J Pharmacol. 2015 Jul;172(14):3484-94. doi: 10.1111/bph.13156. Epub 2015 May 19. PubMed PMID: 25832173; PubMed Central PMCID: PMC4507154.
- Burris SK, Wang Q, Bulley S, Neeb ZP, Jaggar JH. 9-Phenanthrol inhibits recombinant and arterial myocyte TMEM16A channels. Br J Pharmacol. 2015 May;172(10):2459-68. doi: 10.1111/bph.13077. Epub 2015 Mar 24. PubMed PMID: 25573456; PubMed Central PMCID: PMC4409899.
- Sullivan MN, Gonzales AL, Pires PW, Bruhl A, Leo MD, Li W, Oulidi A, Boop FA, Feng Y, Jaggar JH, Welsh DG, Earley S. Localized TRPA1 channel Ca2+ signals stimulated by reactive oxygen species promote cerebral artery dilation. Sci Signal. 2015 Jan 6;8(358):ra2. doi: 10.1126/scisignal.2005659. PubMed PMID: 25564678.
- Samak G, Chaudhry KK, Gangwar R, Narayanan D, Jaggar JH, Rao R. Calcium/Ask1/MKK7/JNK2/c-Src signalling cascade mediates disruption of intestinal epithelial tight junctions by dextran sulfate sodium. Biochem J. 2015 Feb 1;465(3):503-15. doi: 10.1042/BJ20140450. PubMed PMID: 25377781; PubMed Central PMCID: PMC4385020.