Place preference and microdialysis studies with two derivatives of methylphenidate

• Published in: Life sciences (1973) 1996, Vol.58 (24), p.PL345-PL352
• Main Authors: Gatley, S John, Meehan, Susanne M., Chen, Ruoyan, Pan, Dong-Feng, Schechter, Martin D., Dewey, Stephen L.
• Format: Article
• Language: English
• Subjects: Animals; Behavior, Animal - drug effects; Conditioning, Classical; Corpus Striatum - drug effects; Corpus Striatum - metabolism; Dopamine - metabolism; Male; methylphenidate; Methylphenidate - analogs & derivatives; Methylphenidate - pharmacology; Microdialysis; microdialysis studies; Motor Activity - drug effects; place preference; Rats; Rats, Sprague-Dawley
• ISSN: 0024-3205; 1879-0631
• DOI: 10.1016/0024-3205(96)00222-6

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.