RT Journal Article
SR Electronic
T1 Dopamine antagonist effect of verapamil on isolated perfused rabbit ear artery.
JF Journal of Pharmacology and Experimental Therapeutics
JO J Pharmacol Exp Ther
FD American Society for Pharmacology and Experimental Therapeutics
SP 802
OP 805
VO 226
IS 3
A1 Johnson, C E
A1 Steinsland, O S
A1 Scriabine, A
YR 1983
UL http://jpet.aspetjournals.org/content/226/3/802.abstract
AB Rabbit ear arteries were isolated and perfused with Krebs-bicarbonate solution. Brief periods of supramaximal nerve stimulation caused reproducible constriction of the arteries, which was inhibited by dopamine at concentrations ranging from 3.3 X 10(-9) to 3.3 X 10(-7) M. The inhibitory effect of dopamine was antagonized by sulpiride and by verapamil. The dose-response curve to dopamine was shifted to the right by both sulpiride and verapamil, indicative of competitive inhibition. The dopamine antagonist activity of verapamil does not appear to be a consequence of its Ca++ channel inhibitory activity because other calcium antagonists (e.g., nitrendipine and diltiazem) had no similar action.