Dizocilpine and reduced body temperature do not prevent methamphetamine-induced neurotoxicity in the vervet monkey: [11C]WIN 35,428 - positron emission tomography studies.
[11C]WIN 35,428 (WIN), a cocaine analog that binds to the dopamine transporter (DAT), and positron emission tomography (PET) were used to evaluate the potential neuroprotective effects of dizocilpine (MK-801) on methamphetamine (MeAmp) induced neurotoxicity in the striatal dopamine system of the vervet monkey. MK-801 (1 mg/kg, i.m.) was administered 30 min prior to a neurotoxic MeAmp dosage for this species (2 x 2 mg/kg, 4 h apart); control subjects received MeAmp. MK-801 treated subjects were anesthetized by the drug for 6-8 h; throughout that period, a 2-3 degrees C decrease in body temperature was measured. At 1-2 weeks post-MeAmp, decreases of approximately 75% in striatal WIN binding were observed for both MK-801/MeAmp and MeAmp subjects. Thus, in this non-human primate species, the combination of MK-801 pretreatment and reduced body temperature did not provide protection from the MeAmp-induced loss of DAT. Further, the absence of an elevated body temperature during the acute MeAmp exposure period indicated that hyperthermia, per se, was not a necessary concomitant of the MeAmp neurotoxicity profile as has been previously demonstrated in rodents. These results provide evidence that different regulatory factors maintain the integrity of the rodent and primate striatal dopamine systems.
Melega
W P
WP
Department of Molecular and Medical Pharmacology, UCLA School of Medicine, Los Angeles, CA 90095-1735, USA. wmelega@mednet.ucla.edu
Lacan
G
G
Harvey
D C
DC
Huang
S C
SC
Phelps
M E
ME
D000818:Animals; D002250:Carbon Radioisotopes; D002352:Carrier Proteins / Q000378:metabolism; D002522:Chlorocebus aethiops; D003042:Cocaine / Q000031:analogs & derivatives / Q000378:metabolism; D003342:Corpus Striatum / Q000000981:diagnostic imaging / Q000187:drug effects / Q000378:metabolism; D016291:Dizocilpine Maleate / Q000494:pharmacology*; D004298:Dopamine / Q000378:metabolism; D050483:Dopamine Plasma Membrane Transport Proteins; D018765:Dopamine Uptake Inhibitors / Q000378:metabolism / Q000633:toxicity*; D007035:Hypothermia; D008297:Male; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D008694:Methamphetamine / Q000633:toxicity*; D009419:Nerve Tissue Proteins / Q000378:metabolism; D018696:Neuroprotective Agents / Q000494:pharmacology*; D014055:Tomography, Emission-Computed
D002250:Carbon Radioisotopes; D002352:Carrier Proteins; D050483:Dopamine Plasma Membrane Transport Proteins; D018765:Dopamine Uptake Inhibitors; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D009419:Nerve Tissue Proteins; D018696:Neuroprotective Agents; D008694:Methamphetamine; C021279:(1R-(exo,exo))-3-(4-fluorophenyl)-8-methyl-8- azabicyclo(3.2.1)octane-2-carboxylic acid, methyl ester; D016291:Dizocilpine Maleate; D003042:Cocaine; D004298:Dopamine