TY - JOUR
T1 - Thromboxane receptor agonists enhance adrenergic neurotransmission in rabbit isolated mesenteric arteries
AU - Trachte, George J
AU - Stein, E. A.
PY - 1989
Y1 - 1989
N2 - Two thromboxane receptor agonists, carbocyclic thromboxane A2 (CTA) and 9,11-dideoxy-11,9-epoxymethano prostaglandin F(2α) (U46619), were examined for their influence on basal force and electrically induced force of isolated superior mesenteric arterial rings from rabbits. Both CTA and U46619 contracted the arterial rings and augmented contractile responses to electrical stimulation (4-20 Hz). The CTA and U46619 also augmented contractile responses to norepinephrine (P < .05) and enhanced norepinephrine release in response to a 16 Hz electrical stimulation (P < .05). The increases in basal force, neurogenic responses and norepinephrine release were prevented by the thromboxane receptor antagonist, {1S-[1-alpha,2-beta(5Z),3-beta,4-alpha]}-7-[3-[{2- [(phenylamino)carbonyl]hydrazino}methyl]-7-oxabicyclo[2.2.1]hept-2- yl]-5-heptenoic acid. The U46619 was more potent than CTA and had a more consistent effect on norepinephrine release. These results are consistent with the hypothesis that thromboxane receptor agonists augment adrenergic neurogenic responses via thromboxane receptors. The mechanism of the enhanced neurogenic responses involved both pre- and postjunctonal effects of the thromboxane receptor agonists.
AB - Two thromboxane receptor agonists, carbocyclic thromboxane A2 (CTA) and 9,11-dideoxy-11,9-epoxymethano prostaglandin F(2α) (U46619), were examined for their influence on basal force and electrically induced force of isolated superior mesenteric arterial rings from rabbits. Both CTA and U46619 contracted the arterial rings and augmented contractile responses to electrical stimulation (4-20 Hz). The CTA and U46619 also augmented contractile responses to norepinephrine (P < .05) and enhanced norepinephrine release in response to a 16 Hz electrical stimulation (P < .05). The increases in basal force, neurogenic responses and norepinephrine release were prevented by the thromboxane receptor antagonist, {1S-[1-alpha,2-beta(5Z),3-beta,4-alpha]}-7-[3-[{2- [(phenylamino)carbonyl]hydrazino}methyl]-7-oxabicyclo[2.2.1]hept-2- yl]-5-heptenoic acid. The U46619 was more potent than CTA and had a more consistent effect on norepinephrine release. These results are consistent with the hypothesis that thromboxane receptor agonists augment adrenergic neurogenic responses via thromboxane receptors. The mechanism of the enhanced neurogenic responses involved both pre- and postjunctonal effects of the thromboxane receptor agonists.
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M3 - Article
C2 - 2540313
AN - SCOPUS:0024511379
SN - 0022-3565
VL - 249
SP - 216
EP - 220
JO - Journal of Pharmacology and Experimental Therapeutics
JF - Journal of Pharmacology and Experimental Therapeutics
IS - 1
ER -