Pharmacological characterization of grooming induced by a selective NK-1 tachykinin receptor agonist.
Bilateral intranigral administration of the selective NK-1 tachykinin receptor agonist [AcArg6, Sar9, Met(O2)11]SP6-11 (0-1 nmol total bilateral dose) selectively induced grooming in rats. This response was blocked by concurrent intranigral administration of the NK-1 tachykinin receptor antagonist RP 67580 (2 nmol), but not by NK-2 (L-659,877) or NK-3 ([Trp7, beta-Ala8]NKA4-10) antagonists. Pretreatment with systemic opioid (naloxone 1.5 mg/kg) and D1 dopamine (SCH 23390 100 micrograms/kg) receptor antagonists also attenuated tachykinin-induced grooming, which was unaffected by D2 dopamine (sulpiride 30 mg/kg) or 5-HT2A+C (ritanserin 2 mg/kg) antagonists. Grooming induced by intranigral [AcArg6, Sar9, Met(O2)11]SP6-11 was also attenuated by bilateral 6-hydroxydopamine lesions of the substantia nigra. These findings indicate that grooming induced by intranigral tachykinins reflects activation of NK-1 receptors and is dependent upon endogenous dopamine and consequent selective stimulation of D1 dopamine receptors.
Stoessl
A J
AJ
Clinical Neurological Sciences, University of Western Ontario, London, Canada. jstoessl@julian.uwo.ca
Brackstone
M
M
Rajakumar
N
N
Gibson
C J
CJ
D000818:Animals; D065127:Dopamine D2 Receptor Antagonists; D004305:Dose-Response Relationship, Drug; D006120:Grooming / Q000187:drug effects*; D008297:Male; D008636:Mesencephalon / Q000166:cytology / Q000187:drug effects; D009292:Narcotic Antagonists / Q000494:pharmacology; D064729:Neurokinin-1 Receptor Antagonists; D009474:Neurons / Q000187:drug effects; D010446:Peptide Fragments / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D018040:Receptors, Neurokinin-1 / Q000819:agonists*; D012702:Serotonin Antagonists / Q000494:pharmacology; D013373:Substance P / Q000031:analogs & derivatives* / Q000494:pharmacology
D065127:Dopamine D2 Receptor Antagonists; D009292:Narcotic Antagonists; D064729:Neurokinin-1 Receptor Antagonists; D010446:Peptide Fragments; D018040:Receptors, Neurokinin-1; D012702:Serotonin Antagonists; C080168:substance P (6-11), Ac(Arg(6)-Sar(9)-Met(O2)(11))-; D013373:Substance P