Propofol inhibits potassium chloride induced contractions of isolated human umbilical vessels.
OBJECTIVE
We have evaluated the effects of propofol and its relationship with K+ channels on human isolated umbilical vessels.


METHODS
Umbilical vessel rings were suspended in isolated organ baths containing Krebs-Ringer solution. In the first series of experiments the effect of propofol (10(-9)-10(-4) M) was examined in a concentration-dependent manner on umbilical vessels precontracted with KCl (60 mmol). In the second series, these effects were studied in the presence of tetraethylammonium.


RESULTS
A mild contraction was produced by low dose propofol in both precontracted umbilical artery and umbilical vein segments. 10(-4) M propofol caused significant relaxation in both umbilical artery and umbilical vein. The relaxation response was significantly reduced by the addition of 10(-1) M tetraethylammonium.


CONCLUSIONS
These results suggested that the responses of propofol on KCl-induced contractions of both umbilical artery and vein were dose dependent, and this effect involved Ca2+ activated K+ channels.
Caliskan
E
E
Adana Teaching and Medical Research Center, Department of Anaesthesiology, Baskent University, Faculty of Medicine, Adana, Turkey. esra_ertr@yahoo.com
Kayhan
Z
Z
Tufan
H
H
D000704:Analysis of Variance; D018686:Anesthetics, Intravenous / Q000494:pharmacology*; D002121:Calcium Channel Blockers / Q000494:pharmacology*; D015220:Calcium Channels / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions / Q000502:physiology; D006801:Humans; D066298:In Vitro Techniques; D009119:Muscle Contraction / Q000187:drug effects*; D009131:Muscle, Smooth, Vascular / Q000187:drug effects; D026902:Potassium Channel Blockers / Q000494:pharmacology; D015221:Potassium Channels / Q000187:drug effects; D011189:Potassium Chloride / Q000494:pharmacology*; D015742:Propofol / Q000494:pharmacology*; D019789:Tetraethylammonium / Q000494:pharmacology; D013997:Time Factors; D014469:Umbilical Arteries / Q000187:drug effects*; D014470:Umbilical Cord / Q000098:blood supply / Q000187:drug effects; D014471:Umbilical Veins / Q000187:drug effects*; D014661:Vasoconstriction / Q000187:drug effects
D018686:Anesthetics, Intravenous; D002121:Calcium Channel Blockers; D015220:Calcium Channels; D026902:Potassium Channel Blockers; D015221:Potassium Channels; D019789:Tetraethylammonium; D011189:Potassium Chloride; D015742:Propofol