The effect of thromboxane synthetase inhibition on tolerance of skin flaps to secondary ischemia caused by venous obstruction.
The harmful effects of the no-reflow phenomenon on skin flaps were modified by using the thromboxane synthetase inhibitor UK-38,485. Sprague-Dawley rats (N = 134) were subjected to either 3 or 5 hours of secondary venous occlusion occurring 24 hours after a primary ischemic episode of 1 1/2 hours. Within each time period, rats received either saline or UK-38,485 at the primary ischemic episode and/or at the secondary ischemic episode. Flaps treated with UK-38,485 in relation to the period of secondary ischemia had a higher survival rate than control ischemic flaps (p less than 0.01). Those treated only at the end of the primary ischemic episode but prior to the secondary ischemic episode had improved survival rates, but these were not statistically significant. These effects may be explained by the lower thromboxane:prostacyclin ratios at the time of revascularization. The possible interrelationship of the prostanoids with free-radical mechanisms in the no-reflow phenomenon is also discussed.
Mellow
C G
CG
Microsurgery Research Centre, St. Vincent's Hospital, Melbourne, Australia.
Knight
K R
KR
Angel
M F
MF
O'Brien
B M
BM
D000818:Animals; D003250:Constriction; D006085:Graft Survival / Q000187:drug effects*; D007093:Imidazoles / Q000494:pharmacology*; D007511:Ischemia / Q000503:physiopathology*; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D012008:Recurrence; D012867:Skin / Q000098:blood supply*; D013524:Surgical Flaps; D013930:Thromboxane-A Synthase / Q000037:antagonists & inhibitors*; D014680:Veins / Q000503:physiopathology
D007093:Imidazoles; C039242:dazmegrel; D013930:Thromboxane-A Synthase