Dr. Alexander Golub
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Contact Information
Department of Physiology and Biophysics Virginia Commonwealth University P.O. Box 980551 Richmond, Virginia 23298-0551 Fax: 804-828-7382 email: agolub@vcu.edu |
Alexander S. Golub received his Ph.D. from the Institute of Physiology in Novosibirsk, Russia, in 1983. After spending 11 years as a researcher in that institute, he joined the faculty at VCU in 1994.
Research
The most important organs (heart, brain and kidney) require a continuous oxygen supply for their normal performance. Even a brief shortage of oxygen delivery to the tissue may cause a heart attack or stroke, leading to patient disability or death. Oxygen is delivered to tissue by the blood, where it is mainly bound to hemoglobin. Oxygen release from the erythrocytes to tissue occurs in the microvessels, especially capillaries. All transport of oxygen from erythrocytes to the cell mitochondria occurs by the passive physical process called diffusion. Oxygen molecules dissociate from hemoglobin and cross the erythrocyte cytoplasm, and then move through the plasma to the capillary wall, and across it to the interstitial fluid. Finally they cross the cell membrane, internal structures of the cell and the mitochondrion and reach their final destination, the enzyme cytochrome oxidase. This simple picture raises many questions related to mechanisms of oxygen transport in different links of the transport chain. Since the work of August Krogh (1919) these mechanisms were studied using mathematical modeling. Experimental studies of oxygen transport in microcirculation were limited by the lack of reliable methods. Development of the phosphorescence quenching technique has allowed the quantitative determination of oxygen concentrations in microscopic volumes. During the last decade a growing number of publications in the field have reported controversial and paradoxical relationships between convective and diffusional mechanisms of oxygen transport in the tissue. The impact of new knowledge on the existing paradigm of tissue metabolism may be very important for theoretical physiology and for its clinical applications.
Selected Publications
A.S. Golub, V.I. Brod, A.L. Krivoshapkin. (1993) Effects of normobaric hyperoxygenation and perfluorocarbon blood substitute infusion on capillary circulation in skeletal muscle. Sechenov Physiol. J. 79/1:56-63 (Russian). PubMed
A.S. Golub, A.S. Popel, L. Zheng, R.N. Pittman. (1997) Analysis of phosphorescence decay in heterogeneous systems using distributions of quencher concentration. Biophys. J. 73:452-465.
A.S. Golub, R.N. Pittman. (2005) Erythrocyte-associated transients in PO2 revealed in capillaries of rat mesentery. Am. J. Physiol. 288: H2735-H2743.
A.S. Golub, M.C. Barker, R.N. Pittman. (2007) PO2 profiles near arterioles and tissue oxygen consumption in the rat mesentery. Am. J. Physiol. Heart Circ. Physiol. 293:1097-1106, 2007.
A.S. Golub, M.C. Barker, R.N. Pittman. (2008) Microvascular Oxygen Tension in the Rat Mesentery. Am J Physiol Heart Circ Physiol. 294:H21-8.
A.S. Golub, R.N. Pittman. (2008) Problems of PO2 measurements in the microcirculation with the high magnification phosphorescence quenching microscopy. (Submitted)