Vasoconstrictor effect of acetylcholine in veins of the liver.
Intraportal acetylcholine administered to narcotized rats produced atropine-resistant constriction of hepatic veins, which was considerably prevented by phentolamine. Sodium nitroprusside produced a vasodilator effect. Similar results were obtained on isolated venous strip from the portal vein: acetylcholine-induced contraction was reduced by 25-50% in the presence of nicotinic receptor antagonist tubocurarine and cholinergic agonist nicotine and by 10% in the presence of tetrodotoxin. Probably, acetylcholine stimulates synthesis and release of a vasoconstrictor transmitter via nicotinic receptors of endothelial cells and/or portal vascular wall nerve terminals.
Tsybenko
V A
VA
Department of Animal and Human Physiology, Taras Shevchenko Kiev National University.
Yanchuk
P I
PI
Pasichnichenko
O M
OM
Komarenko
V I
VI
Prikhod'ko
T P
TP
D000109:Acetylcholine / Q000494:pharmacology*; D000818:Animals; D001285:Atropine / Q000494:pharmacology; D066298:In Vitro Techniques; D009599:Nitroprusside / Q000494:pharmacology; D010646:Phentolamine / Q000494:pharmacology; D011169:Portal Vein / Q000187:drug effects* / Q000502:physiology; D051381:Rats; D011978:Receptors, Nicotinic / Q000187:drug effects / Q000502:physiology; D014403:Tubocurarine / Q000494:pharmacology; D014661:Vasoconstriction / Q000187:drug effects*
D011978:Receptors, Nicotinic; D009599:Nitroprusside; D001285:Atropine; D000109:Acetylcholine; D014403:Tubocurarine; D010646:Phentolamine