Central administration of p-octopamine to mice: assessment of antinociception.
Administration of p-octopamine by intracerebroventricular (i.c.v.) or intrathecal (i.t.) routes, but not orally, produced antinociception in the acetylcholine-induced abdominal constriction test (ED50 = 24.8 and 3.6 micrograms, respectively). Likewise, i.c.v. and i.t., but not peripheral (up to 200 mg/kg s.c.), administration increased latency in the 48 degrees C hot-plate test (ED50 = 11.5 micrograms i.c.v. and 0.2 micrograms i.t.). These actions were relatively long-lasting and not blocked by naloxone. Antinociception following i.c.v. administration was abolished in reserpinized mice or by pretreatment with i.t. phentolamine (2 micrograms). These results suggest a moderate antinociceptive action of p-octopamine involving non-opioid, reserpine-sensitive, central pathways.
Raffa
R B
RB
Department of Biological Research, Janssen Research Foundation, Spring House, PA 19477-0776.
Mathiasen
J R
JR
Goode
T L
TL
D000700:Analgesics; D000818:Animals; D007276:Injections, Intraventricular; D007278:Injections, Spinal; D008297:Male; D051379:Mice; D009655:Octopamine / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000494:pharmacology; D011930:Reaction Time / Q000187:drug effects
D000700:Analgesics; D009655:Octopamine; C005310:norfenefrine