# Dopamine Concentration Changes Associated with the Retrodialysis of Methylone and 3,4-Methylenedioxypyrovalerone (MDPV) into the Caudate Putamen

## TL;DR

This study shows how two synthetic drugs affect dopamine levels in the brain of rats, using a technique called retrodialysis.

## Contribution

The novel use of in vivo retrodialysis to evaluate the effects of synthetic psychoactive cathinones on dopamine neurotransmission in real time.

## Key findings

- Methylone increased dopamine levels by 200% in rat brains.
- MDPV increased dopamine levels by 470% in rat brains.
- Retrodialysis is effective for studying neurotransmitter changes caused by synthetic drugs.

## Abstract

Structural modifications to synthetic psychoactive cathinones (SPCs), a class of drugs that contain a β-keto modification of the phenethylamine pharmacophore of amphetamine, induce differences in dopamine transporter (DAT) activity. Here, in vivo retrodialysis was utilized to deliver the SPCs 3,4-methylenedioxypyrovalerone (MDPV, a DAT inhibitor) or methylone (a DAT substrate) into the caudate putamen of male Sprague-Dawley rats. Dialysate samples were collected prior to and post drug administration, and temporal changes in dopamine concentration were quantified using HPLC-EC methods. Methylone elicited a 200% increase and MDPV a 470% increase in dopamine levels at the 10 min time point. The findings demonstrate that in vivo retrodialysis can be used to evaluate the effects of SPCs on neurotransmission in the brain.