Irina Grichtchenko, Ph.D. Assistant Professor Department of Physiology & Biophysics
	UCHSC at Fitzsimons RC-1 North Tower, P18-7119 PO Box 6511, Mail Stop F8307 Tel (303) 724-4514 Fax (303) 724-4501	E-mail: irina.grichtchenko@UCHSC.edu Curriculum vitae

CURRENT RESEARCH

Dr. Irina I. Grichtchenko, Assistant Professor, carried out her Ph.D. work at NYU Medical Center, under the direction of Dr. Mitchell Chesler, M.D., Ph.D. (link). She received her Ph.D. in General Physiology in 1995 from Bogomoletz Institute of Physiology in Kiev, Ukraine. 

Her postdoctoral work was done at Yale University in the laboratory of Dr. Walter F. Boron, M.D., PhD.(link).  In the summer of 2002, Dr. Grichtchenko joined the faculty at UCDHSC.

Our laboratory is interested in the cellular and molecular physiology of bicarbonate secretion and absorption in the polarized epithelia tissues and brain. Bicarbonate transport plays equally important roles in the regulation of systemic acid-base homeostasis and the regulation of intracellular pH. The SLC4 and SLC26 gene families of bicarbonate transporters support translocation of acid-base equivalents across the plasma membrane. The hormonal and neurotransmitter agonists of G-protein-coupled receptors (GPCR) control functional activity and membrane trafficking of bicarbonate transporters.

We use Xenopus laevis oocytes and mammalian cells and tissue to study activity and membrane trafficking of bicarbonate transporters regulated by GPCR-mediated signal transduction events.

Xenopus oocytes. We co-express recombinant transporters with recombinant receptors in the readily controlled oocyte expression system. We activate receptors with its agonists and use inhibitors and markers to identify mechanisms of the signal transduction and trafficking regulation of bicarbonate transporters.

By confocal laser scan microscopy in living oocytes we study membrane trafficking of EGFP-tagged bicarbonate transporters using styryl fluorescent dyes and trafficking inhibitors and markers. Fig. 1 shows confocal images of live oocytes expressing NBCe1-EGFP (green) and loaded with endocytotic marker FM4-64 fluorescent dye (red). ANGII induces formation of endosomes co-stained with NBCe1-EGFP and FM4-64 (Zeiss LSM510 microscope, (link), from Perry C, Le H, Grichtchenko II. Am J Physiol Renal Physiol. 2007 Mar 20.)

We also utilize confocal laser scan microscopy to measure Ca²⁺ inside living oocytes loaded with Ca-sensitive fluorescent dye. Fig. 2 illustrates that ANGII increases intracellular Ca²⁺ in oocytes expressing AT1 receptor. Confocal images in live oocytes show increase in Fluo-4 fluorescence. Graph in Fig. 2 shows normalized fluorescence (F/F0) of Fluo4 in oocytes treated with PMA, ANG II, or BAPTA + ANG II. (From Perry C, Blaine J, Le H, Grichtchenko II., Am J Physiol Renal Physiol. 2006.)

Mammalian cells. In our study in mammalian culture cells transfected with EGFP-tagged NBC and in cells with endogenous NBC we use: image 2D deconvolution and laser scan confocal microscopy (Fig. 3) and total internal reflection fluorescence (TIRF) imaging analysis (Fig. 4) (link).

Before Joining Dr. Grichtchenko's laboratory, Mr. Clint Perry (a third-year graduate student) received his B.S. at the University of Pittsburgh in Chemistry in 2000. He then spent three years studying the structure and function of the Epithelial Sodium Channel in the laboratory of Dr. Thomas Kleyman at the University of Pittsburgh  (link), where he co-authored seven scientific papers(link).

Current lab colleagues
Jennifer Hageman - PRA
Clint Perry - Graduate Student
Henry Yamashiro - Visiting Fellow

Selected Publications

Latest Publications in PubMed