verapamil apparent influx permeability clearance in brain 2019-05-22T15:07:20Z CMO:0003170 Kin, brain PMID:24985475 This is a calculated measurement which is used to determine passive permeability coefficients. It helps assess the rate of verapamil permeation and the presence of active transport processes in a two compartment system involving brain and blood plasma. This calculated value is determined by this formula: Capp(t)/Cp(t) = Kin,tissue x AUC(t)/Cp(t) + Vi, where Capp=apparent concentration, p=plasma, and Vi=rapidly equilibrated distribution volume of verapamil in brain. VT:0000075 clinical_measurement_ontology influx rate constant, brain sjwang blood verapamil metabolism measurement