Effect of histamine on human placental chorionic veins: interaction with serotonin.
The vasomotor effects of histamine and its interaction with serotonin were studied in isolated human placental chorionic veins. Histamine induced concentration-dependent contractions with an EC50 of 8.7 +/- 1.2 x 10(-6) mol/l. The H1 antagonist, pyrilamine (10(-9) to 10(-7) mol/l), inhibited histamine-induced contractions, with a pA2 of 8.33 +/- 0.32 at a slope of 0.635. Cimetidine (H2 antagonist) had no effect on histamine-induced contractions. Serotonin (10(-9) to 10(-8) mol/l) significantly potentiated the contractile effect of histamine. The possible implications of the interaction between both amines in the regulation of placental blood flow is discussed.
Cruz
M A
MA
Departamentos de Ciencias Fisiológicas y de Histología y Embriología, Facultad de Ciencias Biológicas y de Recursos Naturales, Universidad de Concepción, Chile.
González
C
C
Sepúlveda
W H
WH
Rudolph
M I
MI
D002823:Chorion / Q000098:blood supply*; D002927:Cimetidine / Q000494:pharmacology; D004347:Drug Interactions; D005260:Female; D006632:Histamine / Q000494:pharmacology*; D006801:Humans; D066298:In Vitro Techniques; D009119:Muscle Contraction / Q000187:drug effects; D009131:Muscle, Smooth, Vascular / Q000187:drug effects*; D010920:Placenta / Q000098:blood supply*; D011247:Pregnancy; D011738:Pyrilamine / Q000494:pharmacology; D012701:Serotonin / Q000494:pharmacology*; D014680:Veins / Q000187:drug effects
D012701:Serotonin; D002927:Cimetidine; D006632:Histamine; D011738:Pyrilamine