PMID- 15529335
OWN - NLM
STAT- MEDLINE
DCOM- 20050425
LR  - 20131121
IS  - 0887-4476 (Print)
IS  - 0887-4476 (Linking)
VI  - 55
IP  - 2
DP  - 2005 Feb
TI  - Mapping interactions between dopamine and adenosine A2a receptors using 
      pharmacologic MRI.
PG  - 80-8
AB  - Adenosine receptors in the basal ganglia are implicated in regulation of dopamine 
      function and release. We investigated the interactions between dopamine receptors 
      and adenosine receptors in the basal ganglia using pharmacologic MRI (phMRI) in 
      rats. Stimulation of dopamine receptors was achieved using administration of 2 
      mg/kg of amphetamine. Then we investigated the antagonism of these changes using 
      the selective A2a receptor antagonist 3,7-dimethyl-1-propargylaxanthine (DMPX). 
      Amphetamine alone caused large increases (10-30%) in relative cerebral blood 
      volume (rCBV) in caudate/putamen (CPu), nucleus accumbens (NAcc), thalamus, and 
      frontal and cingulate cortices with changes that persisted for 70-80 min. DMPX 
      alone (5 mg/kg) induced decreases in rCBV (approximately 8-10%) in NAcc, CPu, and 
      olfactory tubercule, with smaller changes in thalamus (-6%) consistent with the 
      regional distribution of A2a receptors. We examined the interactions between 
      amphetamine and DMPX by assessing the effects of DMPX (5 mg/kg) administration 20 
      min after injection of 3 mg/kg amphetamine. These experiments showed that DMPX 
      immediately decreased the rCBV increase induced by amphetamine in NAcc, CPu, and 
      thalamus but not in cingulate or sensorimotor cortex. Companion microdialysis 
      experiments showed that dopamine release in CPu was decreased in a similar 
      manner. These experiments demonstrate the utility of phMRI for probing, in a 
      noninvasive manner, the temporal and spatial dynamics of neurotransmitter 
      interactions.
FAU - Chen, Y Iris
AU  - Chen YI
AD  - MGH-NMR Center and Athinoula A. Martinos Center for Biomedical Imaging, 
      Massachusetts General Hospital and Harvard Medical School, Charlestown, 
      Massachusetts 02129, USA.
FAU - Choi, Ji-Kyung
AU  - Choi JK
FAU - Jenkins, Bruce G
AU  - Jenkins BG
LA  - eng
GR  - DA-16187A/DA/NIDA NIH HHS/United States
GR  - DA009467/DA/NIDA NIH HHS/United States
PT  - Comparative Study
PT  - Journal Article
PT  - Research Support, U.S. Gov't, P.H.S.
PL  - United States
TA  - Synapse
JT  - Synapse (New York, N.Y.)
JID - 8806914
RN  - 0 (Adenosine A2 Receptor Antagonists)
RN  - 0 (Dopamine Uptake Inhibitors)
RN  - 0 (Receptor, Adenosine A2A)
RN  - 0 (Receptors, Dopamine)
RN  - 5YFR5SPS6T (3,7-dimethyl-1-propargylxanthine)
RN  - OBD445WZ5P (Theobromine)
RN  - TZ47U051FI (Dextroamphetamine)
RN  - VTD58H1Z2X (Dopamine)
SB  - IM
MH  - Adenosine A2 Receptor Antagonists
MH  - Animals
MH  - Blood Volume/drug effects
MH  - Brain/anatomy & histology/drug effects/*physiology
MH  - *Brain Mapping
MH  - Cerebrovascular Circulation/drug effects
MH  - Dextroamphetamine/pharmacology
MH  - Dopamine/metabolism
MH  - Dopamine Uptake Inhibitors/pharmacology
MH  - Drug Interactions
MH  - Magnetic Resonance Imaging/methods
MH  - Male
MH  - Microdialysis/methods
MH  - Rats
MH  - Rats, Sprague-Dawley
MH  - Receptor, Adenosine A2A/*metabolism
MH  - Receptors, Dopamine/*metabolism
MH  - Theobromine/*analogs & derivatives/pharmacology
MH  - Time Factors
EDAT- 2004/11/06 09:00
MHDA- 2005/04/26 09:00
CRDT- 2004/11/06 09:00
PHST- 2004/11/06 09:00 [pubmed]
PHST- 2005/04/26 09:00 [medline]
PHST- 2004/11/06 09:00 [entrez]
AID - 10.1002/syn.20091 [doi]
PST - ppublish
SO  - Synapse. 2005 Feb;55(2):80-8. doi: 10.1002/syn.20091.