Comparison of the contractile effects of an extract of Ginkgo biloba and some neurotransmitters on rabbit isolated vena cava.
Dose-related contractions were elicited in strips of rabbit isolated vena cava by norepinephrine (NE, IC50 approximately equal to 2.3 X 10(-7) M), dopamine (IC50 approximately equal to 6.9 X 10(-6) M), histamine (IC50 approximately equal to 2.1 X 10(-6) M) and extract of Ginkgo biloba (Gb, IC50 approximately equal to 86 micrograms/ml). Serotonin and tyramine elicited very weak contractile effects in this preparation. Phenoxybenzamine (10(-7) M) abolished the contractions elicited by NE, and blocked the effect of Gb by about 50%. Further support is provided for the therapeutic action of Gb in cardiovascular disorders.
Hellegouarch
A
A
Baranès
J
J
Clostre
F
F
Drieu
K
K
Braquet
P
P
DeFeudis
F V
FV
D000818:Animals; D004298:Dopamine / Q000494:pharmacology; D006632:Histamine / Q000494:pharmacology; D066298:In Vitro Techniques; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D009131:Muscle, Smooth, Vascular / Q000187:drug effects*; D018377:Neurotransmitter Agents / Q000494:pharmacology*; D009638:Norepinephrine / Q000494:pharmacology; D010936:Plant Extracts / Q000494:pharmacology*; D011817:Rabbits; D014683:Vena Cava, Superior / Q000187:drug effects
D018377:Neurotransmitter Agents; D010936:Plant Extracts; D006632:Histamine; D004298:Dopamine; D009638:Norepinephrine