Introduction
Experimental
Results
Discussion
PMSF effect on the analgesic latency of acute morphine. The latency of nociceptive responses was measured 60 min after MPH administration. To assess the effects of PMSF on acute morphine-induced antinociception in the hot-plate test, the animals received a dose of PMSF (60 mg/kg, i.p.), 30 min before morphine (10 mg/kg, s.c.). Data are expressed as the means ± SEM. Each group consisted of 8 mice. ***P < 0.001 compared to vehicle control
Effect of acute administration of PMSF on the expression of morphine tolerance in mice. To evaluate whether PMSF could reverse morphine tolerance in mice, the animal received morphine (10 mg/kg, s.c.) twice daily for 10 days and on the test day (day11), PMSF (60 mg/kg, i.p.) was administrated 30 min before morphine injection. The hot-plate test was carried out to evaluate the effect of PMSF on the expression of morphine tolerance. Each point represents the means ± SEM. (n = 8). ***P < 0.001 vs. vehicle-treated group (ANOVA Tukey's multiple comparison test)
Effect of chronic administration of PMSF on the development of tolerance to the analgesic effect of morphine in mice. To evaluate whether PMSF could reverse morphine tolerance in mice, PMSF (60 mg/kg, i.p.) was administered 30 min before morphine (10 mg/kg, s.c.) twice daily for 11 days. The analgesic effect was recorded on the 1st, 3rd, 5th, 7th, 9th, and 11th days, 60 min after morphine injection in the hot-plate test. Each point represents the means ± SEM. (n = 8). **P < 0.01, ***P < 0.001 vs. saline-treated group; ###P < 0.001 vs. morphine alone treated group (Bonferroni's multiple comparison test)
Effect of acute or chronic administration of PMSF on naloxone-induced withdrawal jump and weight loss in morphine-dependent mice. In the chronic study, animals received PMSF (60 mg/kg, i.p.) twice daily for 11 days 30 min before each morphine (10 mg/kg, s.c.) and in the expression phase, animals received PMSF (60 mg/kg, i.p.) on the 11th day, 30 min before last morphine (10 mg/kg, s.c.) injection. Naloxone (4 mg/kg) was injected into mice on the 11th day, 2h after morphine. Each point represents the means ± SEM. (n = 8). ***P < 0.001 vs. morphine treated group alone, ###P < 0.001 vs. vehicle-treated group (ANOVA Tukey's multiple comparisons test)
Effect of the chronic or acute administration of PMSF on naloxone-induced alterations in the brain GPx (A), SOD (B), CAT (C), and GSH (D) levels in morphine-dependent mice. In the chronic study, animals received PMSF (60 mg/kg, i.p. twice daily for 10 days) 30 min before morphine (10 mg/kg, s.c. twice daily for 10 days) and on the 11th in the expression phase, animals received PMSF (60 mg/kg, i.p.) 30 min before last morphine (10 mg/kg, s.c.) injection. In the expression phase, animals received morphine (10 mg/kg, s.c. twice daily for 10 days) and on the 11th day PMSF (60 mg/kg, i.p.) 30 min before last morphine (10 mg/kg, s.c.) injection. Naloxone (4 mg/kg) was injected into mice on the 11th day, 2h after morphine
Effect of chronic or acute administration of PMSF on naloxone-induced alterations in the brain MDA level in morphine-dependent mice. In the chronic study, animals received PMSF (60 mg/kg, i.p. twice daily for 10 days) 30 min before morphine (10 mg/kg, s.c. twice daily for 10 days) and on day 11 in the expression phase, animals received PMSF (60 mg/kg, i.p.) 30 min before last morphine (10 mg/kg, s.c.) injection. In the expression phase, animals received morphine (10 mg/kg, s.c. twice daily for 10 days) and on the 11th day PMSF (60 mg/kg, i.p.) 30 min before last morphine (10 mg/kg, s.c.) injection. Naloxone (4 mg/kg) was injected into mice on the 11th day, 2 h after morphine. Each point represents the means ± SEM. (n = 8). *P < 0.05, **P < 0.01, ***P < 0.001 vs. vehicle-treated group, ###P < 0.001 vs. morphine-treated group, alone. (ANOVA Tukey's multiple comparisons test)







