strain: Wistar pretreatment drug & dose: Methylphenidate (5 mg/kg) cpp conditioning drug and dose: Methylphenidate (5 mg/kg) self-administration (drug volume/infusion): 0.25 mg/0.1 ml infusion, methylphenidate tissue: Striatum
Treatment protocol
Rats were acclimatized to their housing conditions prior to drug or saline administration. Drug treatment (twice daily, intraperitoneal [i.p.]) commenced when rats were 6 weeks old, and lasted for 7 days. Rats were divided into two groups: (cohort 1) 4 groups of rats (n=12 rats per group) given saline only (1 mg/kg, i.p.,”drug-naive” rats); and (cohort 2): 3 groups of rats given either methamphetamine, amphetamine or methylphenidate (5 mg/kg,i.p., “drug-pretreated”) prior to behavioral assays (Conditioned Place Preference and Self-administration tests).
Growth protocol
Male Wistar rats ( 4 weeks old) were obtained from Orient Bio Korea. The animals were housed in an environmentally-controlled animal room (temperature [22 ± 2°C] and humidity- [55 ± 5%], 12 hr/12 hr light/dark [6 AM-6 PM] cycle), in groups (during drug treatment and CPP experiments) and individually thereafter during self-administration tests. All experiments were performed in accordance with the Principles of Laboratory Animal Care (NIH) and the Animal Care and Use Guidelines of Sahmyook University, Korea.
Extracted molecule
total RNA
Extraction protocol
Total RNA was isolated using the Trizol reagent (Invitrogen, Carlsbad, CA, USA), according to the manufacturer's instructions.
Label
biotin
Label protocol
RNA was converted to cDNA and transcribed into cRNA in the presence of biotinylated ribonucleotides, according to standard Affymetrix protocols (Affymetrix ‘Expression Analysis Technical Manual’, #701021 Rev. 5).
Hybridization protocol
Hybridization was carried out using Affymetrix GeneChip Rat Genome 230 2.0 oligonucleotide arrays (Affymetrix, Santa Clara,CA, USA). The hybridized probe array was stained and washed with GeneChip hybridization, wash and stain kit using the Fluidics Station 450 (Affymetrix).
Scan protocol
The stained GeneChip probe array was scanned with a GeneChip Scanner 3000+7G (Affymetrix).
Description
Co2_STR_Mph_1
Data processing
The signal intensity of the gene expression level was calculated by the Expressin Console Software, Version 1.1 (Affymetrix) based on the MAS 5.0 algorithm.
