PMSF (Phenylmethylsulfonyl fluoride) is an irreversible inhibitor of serine/cysteine protease and is often used in the preparation of cell lysates.

Neutrophil:22.8 μg/mL, antinociception (mouse):86 mg/kg (ED50), Neutrophil:95 μM, hypothermia (mouse):224 mg/kg (ED50), Neutrophil:130.9 μM, Remain immobile (mouse):206 mg/kg (ED50)

Treatment with PMSF (intraperitoneal injection) in mice elicits cannabinoid-like effects, providing analgesia (ED50: 86 mg/kg), hypothermia (ED50: 224 mg/kg), and catalepsy (ED50: 206 mg/kg). When administered to Sprague-Dawley rats, PMSF induces a dose-dependent analgesic effect and significantly potentiates the analgesic effect of β-endorphin in vivo. By inhibiting fatty acid amide hydrolase (FAAH) activity, PMSF suppresses typical cannabinoid or Δ(9)-tetrahydrocannabinol-like effects in ICR mice. Pretreatment with 30 mg/kg PMSF before the injection of [3H]-labeled cannabinoids results in a notable increase in brain cannabinoid levels after 5 minutes compared to [3H]-THC. PMSF pretreatment at 30 mg/kg enhances the cannabinoid-induced effects on the tail-flick response (analgesic effect), locomotion, and spontaneous activity by 5, 8, and 10-fold respectively. Administering PMSF 12 hours before paraoxon (PSP) protects hens from delayed neurotoxicity, whereas administration 4 hours later exacerbates the neurotoxic effects. PMSF pretreatment also prevents organophosphate-induced delayed neuropathy in hens and inhibits neuropathilament degeneration induced by tri-ortho-tolyl phosphate.

METHODS: To study the analgesic effect of PMSF, PMSF was intraperitoneally injected into mice.
RESULTS: Mice exhibited cannabinoid effects: including analgesia, hypothermia and immobility, with ED50 values of 86, 224 and 206 mg/kg, respectively.