Research Overview
Theoretical and computational renal physiology
The overall goal of our work is to synthesize experimental data at the membrane and molecular level into predictive mathematical models of the mammalian kidney that are useful in understanding both its normal and diseased function.
Depending on species, the mammalian kidney consists of fifty thousand to one million similar but not identical units, the nephrons, operating in parallel. Each nephron is a tube approximately 1 cm long and 10-3 cm in diameter. The closed end is wrapped around a specialized knot of capillaries to form the glomerulus; the open ends merge to empty into the ureter and thence the bladder. A protein- and cell-free filtrate of blood expressed by the glomerular capillaries is modified as it flows down the nephron by the selective reabsorption of most of the solutes and water and the selective secretion of other solutes. This modified filtrate forms urine in such a way as to maintain the composition of the interstitial fluid bathing the cells of the body within the narrow limits compatible with life.
Our current research is directed along two parallel paths:
1. Incorporation of the details of transcellular transport into models of individual tubular segments. We are particularly interested in the role of Ca2 in regulating Na absorption in cortical collecting tubule and of Mg2 in regulating Na absorption in thick ascending limb.
2. Incorporation of the tubular models into architecturally detailed models of single nephrons and of the whole kidney. Simulation of these extended models lends itself naturally to the vector and parallel processing capabilities of supercomputers, and we have ongoing projects at both the Cornell National Supercomputer Facility and at the State University of New York at Stony Brook.
