Role of gastric mast cells in the regulation of central TRH analog-induced hyperemia in rats.
RX 77368 (RX) increases gastric mucosal blood flow by a vagal cholinergic mechanism. The relative roles of mucosal and connective tissue mast cells (MMC and CTMC) were investigated in RX-injected rats. Blood flow and mast cell degranulation were measured after intracisternal RX. RX significantly increased gastric mucosal blood flow, and sequentially degranulated CTMC and MMC. Ketotifen or doxantrazole inhibited the hyperemic response. Ondansetron, RS-039604-90, or famotidine, but not ketanserin or pyrilamine, reduced hyperemia. Mast cells mediate RX-induced gastric hyperemia via 5-HT3, 5-HT4, and H2 receptors; initial increase depends upon CTMC whereas MMC contributes to the later response.
Kawakubo
Keishi
K
Digestive Diseases Division, CURE: Digestive Diseases Research Center, Department of Medicine, University of California, Los Angeles, CA 90073, USA.
Akiba
Yasutada
Y
Adelson
David
D
Guth
Paul H
PH
Engel
Eli
E
Taché
Yvette
Y
Kaunitz
Jonathan D
JD
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D002452:Cell Count; D015550:Cell Degranulation / Q000187:drug effects; D003239:Connective Tissue Cells / Q000166:cytology; D004205:Cromolyn Sodium / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D005753:Gastric Mucosa / Q000166:cytology; D006633:Histamine Antagonists / Q000494:pharmacology; D006940:Hyperemia / Q000139:chemically induced* / Q000503:physiopathology; D007276:Injections, Intraventricular; D007665:Ketotifen / Q000494:pharmacology; D008297:Male; D008407:Mast Cells / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D011761:Pyrrolidonecarboxylic Acid / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D012039:Regional Blood Flow / Q000187:drug effects; D012702:Serotonin Antagonists / Q000494:pharmacology; D013270:Stomach / Q000166:cytology* / Q000187:drug effects; D013892:Thioxanthenes / Q000494:pharmacology; D013973:Thyrotropin-Releasing Hormone / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000494:pharmacology; D014655:Vascular Resistance / Q000187:drug effects; D044004:Xanthones / Q000494:pharmacology
D006633:Histamine Antagonists; D012702:Serotonin Antagonists; D013892:Thioxanthenes; D044004:Xanthones; D013973:Thyrotropin-Releasing Hormone; C027979:L-pyroglutamyl-L-histidyl-3,3-dimethylprolinamide; D004205:Cromolyn Sodium; D011761:Pyrrolidonecarboxylic Acid; C010134:doxantrazole; D007665:Ketotifen