Place preference and microdialysis studies with two derivatives of methylphenidate.
Conditioned place preference studies with derivatives of dl-threo-methylphenidate (Ritalin) which bear a bromine atom or a methoxy group on the para position of the phenyl ring are reported. Both derivatives, as well as methylphenidate itself, induced a significant increase in place preference when administered i/p to rats at 10 mg/Kg, compared with saline conditioned controls. The change for p-bromomethylphenidate was slightly greater than that seen for methylphenidate or p-methoxymethylphenidate. Extracellular dopamine in the striatum, and locomotor activity, were also increased by i/p administration of p-methoxymethylphenidate (20 mg/Kg) to a similar extent to the increases seen with this dose of methylphenidate or p-bromomethylphenidate in an earlier study (Pan et al. Eur. J. Pharmacol. 264: 177-182, 1994). Administration of p-methoxymethylphenidate failed to abolish increases in extracellular dopamine and locomotor activity induced by subsequent administration of cocaine (20 mg/Kg). It is concluded that the methylphenidate derivatives share the general pharmacological properties of other psychostimulant drugs.
Gatley
S J
SJ
Medical Department, Brookhaven National Laboratory, Upton, NY 11973, USA. gatley@brain.med.bnl.gov
Meehan
S M
SM
Chen
R
R
Pan
D F
DF
Schechter
M D
MD
Dewey
S L
SL
D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects*; D003214:Conditioning, Classical; D003342:Corpus Striatum / Q000187:drug effects / Q000378:metabolism; D004298:Dopamine / Q000378:metabolism; D008297:Male; D008774:Methylphenidate / Q000031:analogs & derivatives / Q000494:pharmacology*; D017551:Microdialysis; D009043:Motor Activity / Q000187:drug effects; D051381:Rats; D017207:Rats, Sprague-Dawley
D008774:Methylphenidate; D004298:Dopamine