This work was aimed at the investigation of the influence of toluene
and ethanol (organic solvents of different strength) on the activity of
opiate receptors in the rat brain hippocampus and the comparison these
results with changes of D2-dopamine receptor activity under the influence
of these solvents.
It has been shown that chronic toluene and alcohol treatment of rats had similar effects on the activity of dopamine and opioid receptors. It was found that both substances upregulated k- and m- opioid receptors and downregulated s-opioid receptors in the hippocampus. In our previous studies it has been shown that both treatments reduce the density of D2-dopamine receptors in N.accumbens and Gl.pallidus.
Thus, according to the data obtained, under the influence of toluene and ethanol, the D2-dopamine receptor, that perceives ventrotegmental projection motivated strengthening reactions in N.accumbens, simultaneously activates with s-opioid receptors in hippocampus. The last one participates in the formation of the behavioral reactions and that is why their coordinated desensitization may be the basis of the behavioral disorders connected with drug addiction.