( ( ( Renal excretion ) ( of ( unchanged prucalopride ) ) ) ( ( involves ( ( ( both ( passive filtration ) ) and ) ( active secretion ) ) ) . ) )
(ROOT (S (NP (NP (JJ Renal) (NN excretion)) (PP (IN of) (NP (JJ unchanged) (NN prucalopride)))) (VP (VBZ involves) (NP (NP (DT both) (JJ passive) (NN filtration)) (CC and) (NP (JJ active) (NN secretion)))) (. .)))
Renal excretion of unchanged prucalopride involves both passive filtration and active secretion.
(ROOT (S (NP (NP (DT The) (JJ main) (NNS functions)) (PP (IN of) (NP (NN epithelia)))) (VP (VBP are) (NP (NP (NN protection)) (PP (IN from) (NP (NP (DT the) (NN environment) (, ,) (NN coverage) (, ,) (NN secretion) (CC and) (NN excretion)) (, ,) (NP (NN absorption)) (, ,) (CC and) (NP (NN filtration)))))) (. .)))