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Tsutomu Suzuki

Faculty of Pharmaceutical Sciences, Shonan University of Medical Sciences, 16-48 Kamishinano, Totsuka-ku, Yokohama, 244-0806, Japan.

3 papers in the library · 14 citations · publishing 2019-2026

Papers

Discriminative Stimulus Effects of Hallucinogenic Drugs: a Possible Relation to Reinforcing and Aversive Effects

Journal of Pharmacological Sciences June 12, 2019 Tomohisa Mori, Kazumi Yoshizawa, Masahiro Shibasaki et al. 13 citations

The subjective effects of drugs, such as euphoria or dysphoria, can be studied using the drug discrimination procedure. Over the past two decades, abuse of hallucinogenic club drugs like PCP, MDMA, LSD, and ketamine has increased, especially among younger people, but the mechanisms behind their discriminative stimulus effects remain unclear. This review of recent animal research identifies at least two plausible mechanisms: one mediated mainly by 5-HT2 receptors, and another mediated through sigma-1 (σ1)-receptor chaperone regulated by an endogenous hallucinogenic ligand.

Possible Involvement of Hallucinogenic Effects in the Aversive Effects Induced by Kappa‐Opioid and 5‐ HT 2A / 2C Receptor Agonists in Mice

Neuropsychopharmacology Reports November 23, 2025 Hideaki Kato, Yoshimi Ichimaru, Masaaki Kurihara et al. 1 citation

A simple behavioral test in mice may help regulators quickly identify new hallucinogenic drugs. Mice given the hallucinogen-like compound DOI showed aversive effects in a conditioned place aversion test and abnormal behavior in a marble-burying test. These responses likely stem from the drug's hallucinogenic properties. The findings suggest that such rodent tests could serve as a rapid, accurate screening method for designating new psychoactive substances as controlled drugs, aiding prevention of drug abuse.

Enhanced effect of the hallucinogen DOI in L-DOPA receptor Gpr143-deficient mice.

Journal of pharmacological sciences June 1, 2026 Daiki Masukawa, Rei Tajika, Yoshimi Ichimaru et al.

Hallucinogens like LSD act mainly through the 5-HT2A receptor, but how they are regulated is not fully understood. GPR143, a receptor for L-DOPA, modulates certain other receptors. In mice lacking GPR143, the hallucinogen DOI caused more hyperactivity and more c-Fos expression in the nucleus accumbens, indicating enhanced effects. In cells expressing the 5-HT2A receptor, adding GPR143 reduced DOI-induced signaling. These results suggest GPR143 dampens 5-HT2A receptor signaling and weakens behavioral responses to hallucinogens.