Transmitter balances in the olfactory cortex: adaptations to early methamphetamine trauma and rearing environment.

The olfactory cortex, comprising the anterior olfactory cortex (AOC) and the anterior piriform cortex (PirC), is a model system for the study of neural plasticity. We investigated the structural imbalances of different transmitter systems induced in this area by an early traumatisation (methamphetamine [MA] intoxication) and/or environmental deprivation (isolated rearing [IR]), with the working hypothesis that such alterations will not occur in an isolated fashion, but in mutual interaction. Indeed, acetylcholine fibre density is increased by IR in both hemispheres of the PirC (left: +22%, p<0.