( Estrogen ( ( ( blocks ( brain ( cell receptors ) ) ) ( for ( ( dopamine , ) ( ( a ( brain-signaling chemical ) ) ( whose ( ( excess activity ) ( is ( linked ( to schizophrenia ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NNP Estrogen)) (VP (VBZ blocks) (NP (NN brain) (NN cell) (NNS receptors)) (PP (IN for) (NP (NP (NN dopamine)) (, ,) (NP (NP (DT a) (JJ brain-signaling) (NN chemical)) (SBAR (WP$ whose) (S (NP (JJ excess) (NN activity)) (VP (VBZ is) (VP (VBN linked) (PP (TO to) (NP (NN schizophrenia))))))))))) (. .)))
Estrogen blocks brain cell receptors for dopamine, a brain-signaling chemical whose excess activity is linked to schizophrenia.
(ROOT (S (NP (NNP Addiction)) (VP (VBZ affects) (NP (NP (DT the) (JJ dopamine) (NNS receptors)) (PP (IN within) (NP (DT the) (NN brain))))) (. .)))