Blockade of 8-OH-DPAT-induced feeding by dopamine antagonists.
Feeding elicited by the 5HT1A agonist 8-OH-DPAT was blocked by pretreatment with the DA antagonists SCH-23390 and sulpiride, in two experiments conducted in non-deprived rats and in three experiments conducted after 4 h food deprivation. In deprived animals, 8-OH-DPAT prolonged the initial period of feeding. However, in non-deprived animals, 8-OH-DPAT delayed the onset of eating, and suppressed post-prandial resting; both SCH-23390 and sulpiride restored the normal pattern of behaviour. All three drugs suppressed grooming. The results suggest that 8-OH-DPAT elicits feeding by a secondary disinhibition of activity postsynaptic to DA neurons. The consequences of this mechanism for the interpretation of 8-OH-DPAT-induced feeding are discussed.
Muscat
R
R
Psychology Department, City of London Polytechnic, UK.
Montgomery
A M
AM
Willner
P
P
D017371:8-Hydroxy-2-(di-n-propylamino)tetralin; D000818:Animals; D001552:Benzazepines / Q000494:pharmacology; D018492:Dopamine Antagonists; D004435:Eating / Q000187:drug effects; D006120:Grooming / Q000187:drug effects; D008297:Male; D009043:Motor Activity / Q000187:drug effects; D009281:Naphthalenes / Q000037:antagonists & inhibitors*; D051381:Rats; D013469:Sulpiride / Q000494:pharmacology; D013764:Tetrahydronaphthalenes / Q000037:antagonists & inhibitors* / Q000494:pharmacology
D001552:Benzazepines; D018492:Dopamine Antagonists; D009281:Naphthalenes; D013764:Tetrahydronaphthalenes; D017371:8-Hydroxy-2-(di-n-propylamino)tetralin; D013469:Sulpiride