Morphine effects on striatal transcriptome in four inbred mouse strains

Chronic opiate use produces molecular and cellular adaptations in the nervous system, leading to tolerance, physical dependence and addiction. Genome-wide comparison of morphine-induced changes in brain transcription of mouse strains with different opioid-related phenotypes provides an opportunity to discover the relationship between gene expression and behavioral response to the drug. Keywords: Drug response Microarray experiment was designed to determine the impact of genetic background on the transcriptional effects of morphine in the striatum. The effects of single (20 mg/kg, s.c.) and repeated morphine administration (10-40 mg/kg, 3 times daily for 5 days) were analyzed in four inbred mouse strains (129P3/J. DBA/2J, C57BL/6J, SWR/J). Twelve experimental groups were compared. Control animals received injections of saline. Three independent biological replicates of the microarray were prepared for each experimental group. For each array, independent pools of total RNA from three animals were prepared.