Disposition Kinetics of Cathinone and its Metabolites after Oral Administration in Rats.

Background: Cathinone is a natural stimulant found in the Catha edulis plant. Its derivatives make up the largest group of new psychoactive substances. In order to better understand its effects, it is imperative to investigate its distribution, pharmacokinetics, and metabolic profile. However, the existing literature on cathinone remains limited.

Objective: This study aimed to investigate the disposition kinetics and metabolic profile of cathinone and its metabolite cathine through a single oral dose of cathinone administration in rats.

Methods: Cathinone and cathine concentrations were identified and quantified using ion trap liquid chromatography- mass spectrometry (LC-IT/MS). The metabolic profile in the serum, brain, lung, liver, kidney, and heart was analyzed at specific time points (0, 0.5, 2.5, 6, 12, 24, 48, and 72 hours) using the ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-QTOF/MS) method.

Results: The highest concentration of cathinone was found in the kidney (1438.6 μg/L, which gradually decreased to 1.97 within 48 h and disappeared after 72 h. Cathinone levels in the lungs, liver, and heart were 859, 798.9, and 385.8 μg/L, respectively, within half an hour. However, within 2.5 hours, these levels decreased to 608.1, 429.3, and 309.1 μg/L and became undetectable after 24 h. In the rat brain, cathinone levels dropped quickly and were undetectable within six hours, decreasing from 712.7 μg/L after 30 min. In the brain and serum, cathine reached its highest levels at 2.5 hours, while in other organs, it peaked at 0.5 hours, indicating slower conversion of cathinone to cathine in the brain and serum.

Conclusion: This study revealed a dynamic interplay between cathinone disposition kinetics and its impact on organ-specific metabolic profiles in rats. These results have significant implications for drug development, pharmacovigilance, and clinical practices involving cathinone. Investigating the correlation between the changes in biomarkers found in the brain and the levels of cathinone and cathine is essential for informed decision- making in medical practices and further research into the pharmacological properties of cathinone.