A pyrazolyl-thiazole derivative causes antinociception in mice
Braz. j. med. biol. res
; 39(6): 795-799, June 2006. graf
Article
in English
| LILACS
| ID: lil-428270
Responsible library:
BR1.1
RESUMO
The present study investigates the antinociceptive effect of the pyrazolyl-thiazole derivative 2-(5-trichloromethyl-5-hydroxy-3-phenyl-4,5-dihydro-1 H-pyrazol-1-yl)-4-(4-bromophenyl)-5-methylthiazole (B50) in mice. Male albino Swiss mice (30-40 g) were used in the acetic acid-induced abdominal writhes and tail-immersion tests. B50 caused dose-dependent antinociception (8, 23 and 80 µmol/kg, sc) in the acetic acid writhing assay (number of writhes vehicle 27.69 ± 6.15; B50 (8 µmol/kg) 16.92 ± 3.84; B50 (23 µmol/kg) 13.85 ± 3.84; B50 (80 µmol/kg) 9.54 ± 3.08; data are reported as means ± SEM for 9 animals per group). On the other hand, B50 did not cause antinociception in the tail immersion assay. Naloxone (2.75 µmol/kg, sc) prevented B50-induced antinociception (number of writhes vehicle-saline 31.11 ± 3.15; vehicle-naloxone 27.41 ± 3.70; B50 (80 µmol/kg)-saline 8.70 ± 3.33; B50 (80 µmol/kg)-naloxone 31.84 ± 4.26; morphine-saline 2.04 ± 3.52; morphine-naloxone 21.11 ± 4.26; 8-9 animals per group). The removal of the methyl group of the thiazole ring of B50 or substitution of the bromo substituent with the methyl at position 4 of the phenyl group, which is attached to the thiazole ring of B50, resulted in loss of activity, suggesting that these substituents are important for antinociceptive activity. B50 had no effect on spontaneous locomotion or rotarod performance, indicating that the antinociceptive effect of B50 is not related to nonspecific motor effects. The antinociceptive profile of B50 seems to be closer to nonsteroidal anti-inflammatory drugs than to classic opioid agents, since it had no analgesic effect in a thermally motivated test.
Full text:
Available
Collection:
International databases
Database:
LILACS
Main subject:
Pyrazoles
/
Thiazoles
/
Pain Measurement
/
Analgesics
Type of study:
Etiology study
Limits:
Animals
Language:
English
Journal:
Braz. j. med. biol. res
Journal subject:
Biology
/
Medicine
Year:
2006
Document type:
Article
/
Project document
Affiliation country:
Brazil
Institution/Affiliation country:
Universidade Federal de Santa Maria/BR