DONALD B. THOMASON, Ph.D., B.A.

Professor
Physiology
 
Dean
Admin-Coll of Grad Health Sci

Office: Ste 807 920 Madison Building
Tel: (901) 448-5538
dthomason@uthsc.edu

Education

  • PostDoc, University of Texas Medical School, Houston, Physiology and cell Biology
  • Ph.D., University of California, Irvine, Physiology and Biophysics
  • Ph.D., University of California, Irvine, Physiology and Biophysics
  • B.A., University of Virginia, Biological Chemistry
  • A.B., University of Virginia, Biological Chemistry

Research description

Although the task of inward potassium transport in muscle is often attributed to the electrogenic Na+-K+ ATPase, a complementary mechanism is Na+-K+-2Cl- cotransporter (NKCC) activity. If coupled with the activity of the Na+-K+ ATPase, NKCC activity provides a much more energy efficient transport of potassium up its concentration gradient than with the Na+-K+ ATPase alone. NKCC activity can be stimulated to contribute as much as one-third of the potassium influx in skeletal muscle. Because of the mass of skeletal muscle, this transport may contribute to whole-body potassium homeostasis. Ongoing studies examine the intracellular mechanism(s) that stimulates NKCC activity to allow potassium uptake by skeletal muscle and how adaptation of NKCC expression affects potassium homeostasis.

Research interest/specialty

G-protein-coupled mechanism of Na-K-2Cl cotransporter-mediated potassium uptake by skeletal muscle.

Research keywords

G-protein, Na-K-2CI, potassium uptake, Na+-K+ATPase, intracellular mechanism(s), NKCC activity, skeletal muscle, potassium homeostasis

Research interest/specialty

G-protein-coupled mechanism of Na-K-2Cl cotransporter-mediated potassium uptake by skeletal muscle.

Research keywords

G-protein, Na-K-2CI, potassium uptake, Na+-K+ATPase, intracellular mechanism(s), NKCC activity, skeletal muscle, potassium homeostasis

Research description

Although the task of inward potassium transport in muscle is often attributed to the electrogenic Na+-K+ ATPase, a complementary mechanism is Na+-K+-2Cl- cotransporter (NKCC) activity. If coupled with the activity of the Na+-K+ ATPase, NKCC activity provides a much more energy efficient transport of potassium up its concentration gradient than with the Na+-K+ ATPase alone. NKCC activity can be stimulated to contribute as much as one-third of the potassium influx in skeletal muscle. Because of the mass of skeletal muscle, this transport may contribute to whole-body potassium homeostasis. Ongoing studies examine the intracellular mechanism(s) that stimulates NKCC activity to allow potassium uptake by skeletal muscle and how adaptation of NKCC expression affects potassium homeostasis.

Publications

  1. Zhou, YW, Thomason, DB, Gullberg, D, Jarrett, HW. Binding of laminin alpha1-chain LG4-5 domain to alpha-dystroglycan causes tyrosine phosphorylation of syntrophin to initiate Rac1 signaling. Biochemistry, 45 (7), 2042-52, 2006.
  2. Gosmanov, AR, Umpierrez, GE, Karabell, AH, Cuervo, R, Thomason, DB. Impaired expression and insulin-stimulated phosphorylation of Akt-2 in muscle of obese patients with atypical diabetes. Am J Physiol Endocrinol Metab, 287 (1), E8-E15, 2004.
  3. Gosmanov, AR, Thomason, DB, Thompson, DB. Regulation of Na(+)-K(+)-2Cl- cotransporter activity in rat skeletal muscle and intestinal epithelial cells. Tsitologiia, 45 (8), 812-6, 2004.
  4. Gosmanov, AR, Fan, Z, Mi, X, Schneider, EG, Thomason, DB. ATP-sensitive potassium channels mediate hyperosmotic stimulation of NKCC in slow-twitch muscle. Am J Physiol Cell Physiol, 286 (3), C586-95, 2004.
  5. Gosmanov, AR, Lindinger, MI, Thomason, DB. Riding the tides: K+ concentration and volume regulation by muscle Na+-K+-2Cl- cotransport activity. News Physiol Sci, 18, 196-200, 2003.
  6. Gosmanov, AR, Schneider, EG, Thomason, DB. NKCC activity restores muscle water during hyperosmotic challenge independent of insulin, ERK, and p38 MAPK. Am J Physiol Regul Integr Comp Physiol, 284 (3), R655-65, 2003.
  7. Gosmanov, AR, Nordtvedt, NC, Brown, R, Thomason, DB. Exercise effects on muscle beta-adrenergic signaling for MAPK-dependent NKCC activity are rapid and persistent. J Appl Physiol, 93 (4), 1457-65, 2002.
  8. Gosmanov, AR, Wong, JA, Thomason, DB. Duality of G protein-coupled mechanisms for beta-adrenergic activation of NKCC activity in skeletal muscle. Am J Physiol Cell Physiol, 283 (4), C1025-32, 2002.
  9. Chockalingam, PS, Cholera, R, Oak, SA, Zheng, Y, Jarrett, HW, Thomason, DB. Dystrophin-glycoprotein complex and Ras and Rho GTPase signaling are altered in muscle atrophy. Am J Physiol Cell Physiol, 283 (2), C500-11, 2002.
  10. Gosmanov, AR, Thomason, DB. Insulin and isoproterenol differentially regulate mitogen-activated protein kinase-dependent Na(+)-K(+)-2Cl(-) cotransporter activity in skeletal muscle. Diabetes, 51 (3), 615-23, 2002.
  11. Wong, JA, Gosmanov, AR, Schneider, EG, Thomason, DB. Insulin-independent, MAPK-dependent stimulation of NKCC activity in skeletal muscle. Am J Physiol Regul Integr Comp Physiol, 281 (2), R561-71, 2001.
  12. Kuykindoll, RJ, Nishimura, H, Thomason, DB, Nishimoto, SK. Osteopontin expression in spontaneously developed neointima in fowl (Gallus gallus). J Exp Biol, 203 (Pt 2), 273-82, 2000.
  13. Wong, JA, Fu, L, Schneider, EG, Thomason, DB. Molecular and functional evidence for Na(+)-K(+)-2Cl(-) cotransporter expression in rat skeletal muscle. Am J Physiol, 277 (1 Pt 2), R154-61, 1999.
  14. Fu, L, Wong, JA, Schneider, EG, Thomason, DB. Unique 5'-end of a Na(+)-K(+)-2Cl- cotransporter-like mRNA expressed in rat skeletal muscle. DNA Seq, 10 (2), 127-32, 1999.
  15. Lima, JJ, Thomason, DB, Mohamed, MH, Eberle, LV, Self, TH, Johnson, JA. Impact of genetic polymorphisms of the beta2-adrenergic receptor on albuterol bronchodilator pharmacodynamics. Clin Pharmacol Ther, 65 (5), 519-25, 1999.
  16. Thomason, DB. Translational control of gene expression in muscle. Exerc Sport Sci Rev, 26, 165-90, 1998.
  17. Thomason, DB, Anderson, O, Menon, V. Fractal analysis of cytoskeleton rearrangement in cardiac muscle during head-down tilt. J Appl Physiol, 81 (4), 1522-7, 1996.
  18. Dunlap, AW, Thomason, DB, Menon, V, Hofmann, PA. Decreased Ca2+ sensitivity of isometric tension in skinned cardiac myocytes from tail-suspended rats. J Appl Physiol, 80 (5), 1612-7, 1996.
  19. Menon, V, Thomason, DB. Head-down tilt increases rat cardiac muscle eIF-2 alpha phosphorylation. Am J Physiol, 269 (3 Pt 1), C802-4, 1995.
  20. Menon, V, Yang, J, Ku, Z, Thomason, DB. Decrease in heart peptide initiation during head-down tilt may be modulated by HSP-70. Am J Physiol, 268 (6 Pt 1), C1375-80, 1995.
  21. Ku, Z, Yang, J, Menon, V, Thomason, DB. Decreased polysomal HSP-70 may slow polypeptide elongation during skeletal muscle atrophy. Am J Physiol, 268 (6 Pt 1), C1369-74, 1995.
  22. Ku, Z, Thomason, DB. Soleus muscle nascent polypeptide chain elongation slows protein synthesis rate during non-weight-bearing activity. Am J Physiol, 267 (1 Pt 1), C115-26, 1994.
  23. Yang, J, Thomason, DB. An easily synthesized, photolyzable luciferase substrate for in vivo luciferase activity measurement. Biotechniques, 15 (5), 848-50, 1993.