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: ["Disease", "Chemical"].

Please return the output as a JSON object of the format: {"Chemical" : ["Naloxone", ...], "Disease" : ["Hypotensive", ...]}. 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:

Dexmedetomidine, acting through central alpha-2 adrenoceptors, prevents opiate-induced muscle rigidity in the rat. The highly-selective alpha-2 adrenergic agonist dexmedetomidine (D-MED) is capable of inducing muscle flaccidity and anesthesia in rats and dogs. Intense generalized muscle rigidity is an undesirable side effect of potent opiate agonists. Although the neurochemistry of opiate-induced rigidity has yet to be fully elucidated, recent work suggests a role for a central adrenergic mechanism. In the present study, the authors determined if treatment with D-MED prevents the muscle rigidity caused by high-dose alfentanil anesthesia in the rat. Animals (n = 42) were treated intraperitoneally with one of the following six regimens: 1) L-MED (the inactive L-isomer of medetomidine), 30 micrograms/kg; 2) D-MED, 10 micrograms/kg; 3) D-MED, 30 micrograms/kg; 4) D-MED [30 micrograms/kg] and the central-acting alpha-2 antagonist, idazoxan [10 mg/kg]; 5) D-MED [30 micrograms/kg] and the peripheral-acting alpha-2 antagonist DG-5128 [10 mg/kg], or; 6) saline. Baseline electromyographic activity was recorded from the gastrocnemius muscle before and after drug treatment. Each rat was then injected with alfentanil (ALF, 0.5 mg/kg sc). ALF injection resulted in a marked increase in hindlimb EMG activity in the L-MED treatment group which was indistinguishable from that seen in animals treated with saline. In contrast, D-MED prevented alfentanil-induced muscle rigidity in a dose-dependent fashion. The small EMG values obtained in the high-dose D-MED group were comparable with those recorded in earlier studies from control animals not given any opiate. The high-dose D-MED animals were flaccid, akinetic, and lacked a startle response during the entire experimental period.(ABSTRACT TRUNCATED AT 250 WORDS)
{"Chemical": ["medetomidine", "alfentanil", "DG-5128", "ALF", "Dexmedetomidine", "dexmedetomidine", "idazoxan", "D-MED"], "Disease": ["muscle rigidity", "akinetic", "muscle flaccidity", "startle", "rigidity"]}