Differential analgesic actions of serotonin 5-HT3 receptor antagonists in the mouse.
The present study examined the analgesic effects of the serotonin 5-HT3 receptor antagonists ICS-205-930, MDL-7222 and GR-38032F in mice using acute thermal, mechanical and chemical pain tests. Subcutaneous administration (1-10 mg/kg) of these agents did not produce analgesia in either the thermal or mechanical pain tests. However, ICS-205-930, MDL-72222 and GR-38032F all produced dose-dependent analgesia in the chemical pain test, that was not altered by systemic naloxone administration (1 mg/kg, s.c.). Intracerebroventricular administration of these drugs (0.1-10 micrograms) was ineffective in producing analgesia in acute thermal, mechanical and chemical pain tests. These results suggest that peripheral 5-HT3 receptors play a role in chemical, but not thermal or mechanical nociceptive mechanisms.
Giordano
J
J
Neuropharmacology Laboratory College of Pharmacy and Health Sciences, Drake University, Des Moines, Iowa 50311.
Dyche
J
J
D000700:Analgesics; D000818:Animals; D007093:Imidazoles / Q000008:administration & dosage / Q000494:pharmacology; D007211:Indoles / Q000008:administration & dosage / Q000494:pharmacology; D007276:Injections, Intraventricular; D008297:Male; D051379:Mice; D008809:Mice, Inbred C3H; D009270:Naloxone / Q000494:pharmacology; D009619:Nociceptors / Q000187:drug effects; D017294:Ondansetron; D010147:Pain Measurement; D011930:Reaction Time / Q000187:drug effects; D012702:Serotonin Antagonists / Q000008:administration & dosage / Q000494:pharmacology*; D014326:Tropanes / Q000008:administration & dosage / Q000494:pharmacology; D000077526:Tropisetron
D000700:Analgesics; D007093:Imidazoles; D007211:Indoles; D012702:Serotonin Antagonists; D014326:Tropanes; D009270:Naloxone; D017294:Ondansetron; D000077526:Tropisetron; C042253:bemesetron