Tissue remodeling of rat pulmonary artery in hypoxic breathing. I. Changes of morphology, zero-stress state, and gene expression

The remodeling of the pulmonary arterial tissue in response to a step change of the oxygen concentration in the gas in which a rat lives was recorded as function of time and function of O-2 concentration. Three steps of changing rom 20.9% to 17.2%, 13.6%, and 10% O-2 were imposed. Earlier work in our laboratory has shown that pulmonary arterial tissue remodeling is significant in the first 24 h after a step change of oxygen tension. Hence we made measurements in this period. Furthermore, data were obtained for tissue remodeling of circumferential and axial lengths of the pulmonary arteries. We recorded the activities of gone expressions in the lung tissues by microarray, determined the dose response curves of gene expression in the homogenized whole lungs with respect to four levels Of O-2 concentration, and obtained the time courses of gene expression in the lung parenchyma in 30 days after a step decrease Of O-2 concentration from 20.9% to 10%. We would like to suggest that the correlation of gene expression with physiological function parameters, i.e., time, O-2 tension, blood pressure, opening angle, wall thicknesses, etc., is the way to narrow down the search for specific genes for specific physiological functions. (C) 2001 Biomedical Engineering Society.