Effect of histamine on human bronchial arteries in vitro.
Histamine caused a concentration-dependent relaxation at lower concentrations (1 pmol/l-1 mumol/l) and contraction at higher concentrations (0.01-1 mmol/l) of isolated precontracted human bronchial arteries. In the vessels at resting tension only concentration-dependent contraction was evoked by histamine (0.01-1 mmol/l). Both the contractile and relaxant responses were significantly antagonised by mepyramine (1 mumol/l), with an estimated pKB value of 8.4, but not by cimetidine (100 mumol/l). Our results indicate that histamine induces biphasic effects on human bronchial arteries via H1-receptors.
Liu
S F
SF
Department of Thoracic Medicine, National Heart and Lung Institute, London, UK.
Yacoub
M
M
Barnes
P J
PJ
D000328:Adult; D001981:Bronchial Arteries / Q000187:drug effects*; D002927:Cimetidine / Q000494:pharmacology; D015237:Dinoprost / Q000494:pharmacology; D006632:Histamine / Q000494:pharmacology*; D006801:Humans; D066298:In Vitro Techniques; D008875:Middle Aged; D009119:Muscle Contraction / Q000187:drug effects; D009126:Muscle Relaxation / Q000187:drug effects; D009131:Muscle, Smooth, Vascular / Q000187:drug effects*; D011738:Pyrilamine / Q000494:pharmacology
D002927:Cimetidine; D006632:Histamine; D015237:Dinoprost; D011738:Pyrilamine