Release of mast cell mediators, vasoconstriction and edema in the isolated, perfused head of the rat following intracarotid infusion of neurotensin.
Intracarotid infusions of neurotensin (NT) into the isolated, perfused head of rats trigger concentration-dependent histamine and 5-hydroxytryptamine (5-HT) release from the perfused organ. The secretory event was accompanied by a concentration-dependent rise in perfusion pressure and facilitation of edema formation. The three NT effects were markedly reduced in heads derived from rats pretreated with high doses of compound 48/80 to produce mast cell depletion. The vasoconstrictor response to NT was greatly attenuated by the 5-HT receptor antagonist methysergide but unaffected by antihistaminic drugs. The results were interpreted as an indication that NT stimulates histamine and 5-HT release from mast cells of the rat perfused head. The results also suggest that the vasoconstrictor response to NT in the rat head is mediated by mast cell 5-HT. The potentiation of edema formation by NT was attributed to the action of mast cell mediators (most likely histamine and 5-HT) released by NT on microvessels.
Rioux
F
F
Kérouac
R
R
St-Pierre
S
S
D000818:Animals; D004205:Cromolyn Sodium / Q000494:pharmacology; D004487:Edema / Q000139:chemically induced; D006257:Head / Q000098:blood supply; D006636:Histamine Release / Q000187:drug effects; D007263:Infusions, Parenteral; D008297:Male; D008407:Mast Cells / Q000187:drug effects*; D009496:Neurotensin / Q000008:administration & dosage / Q000494:pharmacology*; D010477:Perfusion; D051381:Rats; D011919:Rats, Inbred Strains; D012039:Regional Blood Flow / Q000187:drug effects; D012701:Serotonin / Q000378:metabolism; D013997:Time Factors; D014661:Vasoconstriction / Q000187:drug effects*; D003189:p-Methoxy-N-methylphenethylamine / Q000494:pharmacology
D012701:Serotonin; D009496:Neurotensin; D003189:p-Methoxy-N-methylphenethylamine; D004205:Cromolyn Sodium