httk (version 1.3)

calc_vdist: Calculate the volume of distribution for a one compartment model.

Description

This function predicts partition coefficients for all tissues, then lumps them into a single compartment. The effective volume of distribution is calculated by summing each tissues volume times it's partition coefficient relative to plasma. Plasma, and the paritioning into RBCs are also added to get the total volume of distribution in L/KG BW. Partition coefficients are calculated using Schmitt's (2008) method.

Usage

calc_vdist(chem.cas=NULL, chem.name=NULL, parameters=NULL,
                           default.to.human=F,species="Human", suppress.messages=F)

Arguments

chem.name

Either the chemical name or the CAS number must be specified.

chem.cas

Either the CAS number or the chemical name must be specified.

parameters

Parameters from parameterize_3comp or parameterize_pbtk.

default.to.human

Substitutes missing animal values with human values if true.

species

Species desired (either "Rat", "Rabbit", "Dog", "Mouse", or default "Human").

suppress.messages

Whether or not the output message is suppressed.

Value

• Volume of distribution
  Units of L/ kg BW.

Details

When species is specified as rabbit, dog, or mouse, the function uses the appropriate physiological data(volumes and flows) but substitues human fraction unbound, partition coefficients, and intrinsic hepatic clearance.

References

Schmitt W. "General approach for the calculation of tissue to plasma partition coefficients." Toxicology In Vitro, 22, 457-467 (2008). Peyret, T., Poulin, P., Krishnan, K., "A unified algorithm for predicting partition coefficients for PBPK modeling of drugs and environmental chemicals." Toxicology and Applied Pharmacology, 249, 197-207 (2010).

Examples

calc_vdist(chem.cas="80-05-7")
calc_vdist(chem.name="Bisphenol A")
calc_vdist(chem.name="Bisphenol A",species="Rat")
calc_vdist(chem.name="Bisphenol A",species="Rabbit")