Endothelial injury provokes collateral arterial vasoconstriction: response to a serotonin 2 antagonist, thromboxane antagonist or synthetase inhibition.
To assess the influence on collateral arteries of vasoactive factors released from activated platelets we used angiography and blood flow measurement to study the limb blood supply in 29 rabbits, 2 weeks after superficial femoral artery ligation. Minutes after balloon catheter injury to the lower aorta, striking spasm of the collateral arteries was routinely evident on the arteriograms, and limb blood flow fell. Spasm was partly reversed either by blockade of thromboxane synthesis (UK-38,485) or its vascular action (SQ 29,548) or by ketanserin, the serotonin receptor antagonist when used alone. Ketanserin combined with either UK-38,485 or SQ 29,548 reversed the spasm completely. We conclude that a combined action of serotonin and thromboxane induces collateral artery spasm when platelets are activated.
Hollenberg
N K
NK
Department of Radiology, Brigham and Women's Hospital, Boston, Massachusetts.
Monteiro
K
K
Sandor
T
T
D000818:Animals; D001792:Blood Platelets / Q000502:physiology; D019086:Bridged Bicyclo Compounds, Heterocyclic; D003097:Collateral Circulation; D004730:Endothelium, Vascular / Q000502:physiology*; D005121:Extremities / Q000098:blood supply; D005231:Fatty Acids, Unsaturated; D006834:Hydrazines / Q000494:pharmacology; D007093:Imidazoles / Q000494:pharmacology; D007650:Ketanserin / Q000494:pharmacology; D011817:Rabbits; D012702:Serotonin Antagonists / Q000494:pharmacology*; D013045:Species Specificity; D013930:Thromboxane-A Synthase / Q000037:antagonists & inhibitors*; D013931:Thromboxanes / Q000037:antagonists & inhibitors*; D014661:Vasoconstriction / Q000187:drug effects*
D019086:Bridged Bicyclo Compounds, Heterocyclic; D005231:Fatty Acids, Unsaturated; D006834:Hydrazines; D007093:Imidazoles; D012702:Serotonin Antagonists; D013931:Thromboxanes; C039242:dazmegrel; C045749:SQ 29548; D007650:Ketanserin; D013930:Thromboxane-A Synthase