Involvement of DA1 and DA2 receptors in the gastroprotective activity of amylin in the rat.
Peripheral administration of amylin (40 microg kg-1) exerts gastroprotective effects in the reserpine-induced gastric lesions in the rat. This activity is decreased by pretreatment (30 min before) with (-)-sulpiride (0.1 mg kg-1 s.c.) or domperidone (0.1-2.5 mg kg-1 per os), dopamine DA2 antagonists. Pretreatment with SCH 23390 (0.5-4 mg kg-1 s.c.), a DA1 antagonist, at the maximal dose used, also significantly decreased the gastroprotective activity of the peptide. Amylin does not exert any gastroprotective effect in indomethacin-pretreated rats (7.5 mg kg-1 s.c., 30 min before), as well as in the aspirin-induced ulcer test (200 mg kg-1 per os at the time of amylin administration). Our data confirm that the gastroprotective effect of amylin in reserpine-induced gastric lesions involves, at least in part, the dopaminergic transmission, interfering with both the DA1 and DA2 receptor subtypes.
Institute of Pharmacology, University of Catania School of Medicine, viale Andrea Doria 6, Catania, 95125, Italy.
G
G
Clementi
A
A
Caruso
V M
VM
Cutuli
E
E
De Bernardis
A
A
Prato
M
M
Amico-Roxas
D000682:Amyloid / Q000494:pharmacology*; D000818:Animals; D000897:Anti-Ulcer Agents / Q000494:pharmacology*; D001552:Benzazepines / Q000494:pharmacology; D004294:Domperidone / Q000494:pharmacology; D005753:Gastric Mucosa / Q000187:drug effects*; D058228:Islet Amyloid Polypeptide; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D017447:Receptors, Dopamine D1 / Q000187:drug effects / Q000502:physiology*; D017448:Receptors, Dopamine D2 / Q000187:drug effects / Q000502:physiology*; D012110:Reserpine / Q000633:toxicity; D013469:Sulpiride / Q000494:pharmacology
D000682:Amyloid; D000897:Anti-Ulcer Agents; D001552:Benzazepines; D058228:Islet Amyloid Polypeptide; D017447:Receptors, Dopamine D1; D017448:Receptors, Dopamine D2; D004294:Domperidone; D013469:Sulpiride; D012110:Reserpine