You will be shown an abstract from a biomedical research paper. Given this abstract, your task is to extract all unique entities of the following types: ["Protein", "Chemical"].

Please return the output as a JSON object of the format: {"Chemical" : ["Dexamethasone", ...], "Protein" : ["BRCA-1", ...]}. The keys should be entity types and values should be lists of extracted entities belonging to the corresponding type. If you cannot find entities belonging to a specific type, the value should be [].

Only output the JSON object and do not include any additional text.

Abstract:

Dopamine D2/3 receptor binding potential and occupancy in midbrain and temporal cortex by haloperidol, olanzapine and clozapine.
AIMS: Aberrant dopamine transmission in extrastriatal brain regions has been repeatedly illustrated among patients with schizophrenia. Differences between typical and second-generation antipsychotics in dopamine D(2) receptor modulation within various brain areas remain a topic for debate. The aim of the present study was therefore to investigate dopamine D(2/3) receptor apparent binding potential (BP(app)) and occupancy in midbrain and temporal cortex among clozapine-, olanzapine- and haloperidol-treated schizophrenia patients. METHODS: Dopamine D(2/3) binding was studied on single-photon emission computed tomography ligand [(123)I]epidepride in 13 schizophrenia patients treated with medication (two with haloperidol, four with olanzapine and seven with clozapine), six drug-naive patients and seven healthy controls. RESULTS: Statistically significant differences in midbrain dopamine D(2/3) receptor BP(app) (P = 0.015) and occupancy (P = 0.016) were observed between the clozapine, olanzapine and haloperidol groups. The lowest occupancy was found in clozapine-treated patients (5%), followed by olanzapine-treated patients (28%), compared to haloperidol-treated patients (40%). No significant differences were observed in the temporal poles. Occupancy changed substantially depending on the comparison group used (either drug-naive vs healthy controls) in the examined brain areas (P = 0.001), showing an overestimation with all antipsychotics when the healthy control group was used. CONCLUSION: Both typical and second-generation antipsychotics occupy cortical dopamine D(2/3) receptors, thus mediating therapeutic efficacy. Observed differences in midbrain dopamine D(2/3) occupancy between classical antipsychotics and second-generation antipsychotics may have clinical relevance by modulating altered nigrostriatal dopamine neurotransmission during the acute phase of schizophrenia.
{"Chemical": ["dopamine", "haloperidol", "olanzapine", "[(123)I]epidepride", "Dopamine", "clozapine"], "Protein": ["dopamine D(2/3)", "dopamine D(2/3) receptors", "dopamine D(2) receptor", "Dopamine D(2/3)", "dopamine D(2/3) receptor", "Dopamine D2/3 receptor"]}