Skip to content

Ján Kehr

Karolinska Institutet

2 papers in the library · publishing 2011-2025

Papers

The psychedelic phenethylamine 25C-NBF, a selective 5-HT2A agonist, shows psychoplastogenic properties and rapid antidepressant effects in male rodents

Molecular Psychiatry November 14, 2025 Núria Nadal‐gratacós, Pol Puigseslloses, Laura Hernández‐guzmán et al.

Three novel phenethylamine derivatives—25C-NBF, 25B-NBF, and 25I-NBF—show high affinity and selectivity for the 5-HT2A receptor, with signaling bias toward Gq over β-arrestin pathways similar to serotonin. In mice, they cause moderate head-twitch responses without affecting movement or sensorimotor gating. No rewarding or reinforcing effects were observed, and accumbal dopamine levels in rats remained unchanged. 25C-NBF promotes dendritogenesis, spinogenesis, and increased Bdnf mRNA in vitro and in vivo, reduces despair-like behavior after acute stress, and produces rapid antidepressant effects in a chronic corticosterone model of anhedonia. These findings suggest 25C-NBF may offer a fast-acting antidepressant with no abuse potential or sensorimotor deficits.

Mephedrone, compared with MDMA (ecstasy) and amphetamine, rapidly increases both dopamine and 5-HT levels in nucleus accumbens of awake rats

British Journal of Pharmacology May 26, 2011 Ján Kehr, Fumio Ichinose, Shimako Yoshitake et al.

The designer drug mephedrone, compared with MDMA (ecstasy) and amphetamine in rats, rapidly increased dopamine levels in the nucleus accumbens by 496% and serotonin levels by 941%, closely matching MDMA's serotonin release but also producing an amphetamine-like fast dopamine surge and elimination. Amphetamine raised dopamine by 412% and serotonin by only 165%. Mephedrone's dopamine levels cleared within 25 minutes, versus 303 minutes for MDMA, suggesting its brief but potent effect on the brain's reward system may underlie strong addictive potential. Locomotor activity increased most with amphetamine; mephedrone and MDMA had weaker, shorter effects.