Parallel tube model, clearance

KS Pang, M Rowland. Hepatic clearance of drugs. I. Theoretical considerations of a well-stirred model and a parallel tube model. Influence of hepatic blood flow, plasma and blood cell binding, and the hepatocellular enzymatic activity on hepatic drug clearance. J Pharmacokin Biopharm 5/6 625-653, 1977. 

Pang KS, Rowland M. Hepatic clearance of drugs. II. Experimental evidence for acceptance of the well-stirred model over the parallel tube model using lidocaine in the perfused rat liver in situ preparation. J Pharmacokinet Biopharm 1977b 5 655-680. 

Parallel tube model V > Overestimate organ clearance for highly extracted drugs... 

Steady state the hepatic intrinsic clearance of pravastatin, a substrate for OATP2 and MRP2 (Tokui et al., 1999 Yamazaki et al., 1997), was regulated by the uptake process, followed by rapid metabolism and/or biliary excretion with minimal efflux to the systemic circulation in rats after infusion. The total hepatic elimination rate at steady state exhibited Michaelis-Menton saturation with the drug concentration and the and V ax obtained in rats with different mathematical models (i.e., well stirred, parallel tube, and dispersion models) were comparable with the initial uptake velocity measured from in vitro hepatocytes (Tokui et al., 1999). 

Yamamoto T, Itoga H, Kohno Y, Nagata K, Yamazoe Y. Prediction of oral clearance from in vitro metabolic data using recombinant CYPs Comparison among well-stirred, parallel-tube, distributed and dispersion models. Xenobiotica 2005 35 627-646. 

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