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: ["Outcome", "Participant", "Intervention"].

Please return the output as a JSON object of the format: {"Participant" : ["patients with COPD", ...], "Intervention" : ["Atenolol", ...], "Outcome" : ["blood pressure", ...]}. 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:

Interactive effects of indomethacin , angiotensin II and frusemide on renal haemodynamics and natriuresis in man . The responses of renal haemodynamic and natriuretic indices to the oral prostaglandin synthetase inhibitor indomethacin ( 200 mg ) , to infused angiotensin II ( 1 ng min-1 kg-1 ) and to the combination of the two were studies in placebo-controlled fashion in eight normal male subjects both prior to and following administration of intravenous frusemide ( 20 mg ) . As compared with placebo , angiotensin II infusion alone caused significant reductions in absolute rate of sodium excretion , fractional sodium excretion , urine flow rate and effective renal plasma flow ( all P < 0.001 vs placebo ) but had no effect on glomerular filtration rate . The only change observed in these parameters with indomethacin alone was a small but significant reduction in urine flow rate ( P < 0.005 vs placebo ) . As compared with the effects of angiotensin II alone , indomethacin pre-treatment followed by angiotensin II infusion led to much greater falls in absolute rate of sodium excretion , fractional sodium excretion , urine flow rate and effective renal plasma flow ( all P < 0.0001 vs placebo ) associated with a significant reduction in glomerular filtration rate ( P < 0.0001 ) not observed with angiotensin II alone . Frusemide administration at the midpoint of each study limb resulted in each case in a prompt 15 to 20 fold increase in natriuresis . The renal haemodynamic and natriuretic effects of angiotensin II , indomethacin and their combination were not qualitatively different from those observed in the pre-frusemide phase . Our findings provide a clear demonstration in man of the important homeostatic role of renal prostaglandins in preserving renal function , particularly glomerular filtration , under conditions of elevated circulating angiotensin II .
{"Intervention": ["Frusemide", "placebo", "pre-frusemide", "frusemide", "infused angiotensin II", "indomethacin", "placebo-controlled", "angiotensin II infusion", "intravenous frusemide", "indomethacin ( 200 mg )", "angiotensin II"], "Outcome": ["natriuresis", "renal haemodynamic and natriuretic effects", "renal function , particularly glomerular filtration", "effective renal plasma flow", "glomerular filtration rate", "homeostatic role", "urine flow rate", "absolute rate of sodium excretion", "fractional sodium excretion"], "Participant": ["eight", "male"]}