Computer-Assisted Analysis of Fluxes of Ions and Other Substances
The models which have been proposed to account for tracer movements in smooth muscle have been discussed elsewhere in this book. For our purposes, we will accept the conclusion that tracer loss proceeds exponentially from a number of compartments (Harris and Burn, 1949), although it should be noted that other solutions, for example, a simple expression involving powers of time, may provide as good a fit to the observed data as an exponential expansion (Anderson et al., 1969). In general, then, the purpose of the mathematical analysis of efflux data is to obtain physiologically meaningful constants which describe tracer movements between the tissue and the external medium. Before embarking on a discussion of computer-assisted techniques to achieve these ends, it is necessary to point out that the success of this approach depends critically on the validity of the model and the accuracy of the experimental data. The best that the computer can do is to provide estimates of the parameters for a given model, together with some data as to the error of the estimate. The widespread notions that the processing of the data by computer either validates the model or compensates for inadequate experimental design are, of course, totally incorrect.
KeywordsCompartmental Analysis Semilogarithmic Plot Compartment Size Efflux Experiment Efflux Data
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