Indomethacin-induced reduction in neonatal piglet mesenteric blood flow is blunted by dopexamine.
BACKGROUND
Dopexamine is a specific dopaminergic and beta2-adrenergic agonist. Using newborn piglets, we have previously shown that (1) dopexamine increases cardiac output and mesenteric blood flow; (2) indomethacin reduces mesenteric blood flow.


METHODS
Ultrasonic blood flow probes were placed around the ascending aorta, cranial mesenteric artery, and a renal artery of 0 to 2-day-old and 2-week-old piglets. Animals of each age were grouped (5 to 8 animals per group) and subjected to one of three experimental protocols: (1) 0.4 mg/kg indomethacin infusion, (2) 10 microg/kg/min dopexamine infusion begun 10 minutes before indomethacin, or (3) no treatment.


RESULTS
Control animals demonstrated no significant alterations in mesenteric blood flow. Compared with baseline, indomethacin produced significant (P< .05, analysis of variance) declines in cranial mesenteric artery blood flow in 0 to 2-day old (37.2+/-5.7 mL/min v 17.9+/-3.7 mL/min at 90 min), and 2-week-old (80.2+/-12.5 mL/min v 29.7+/-5.7 mL/min at 90 minutes) piglets. In both animal groups treated with dopexamine before indomethacin, the decreases in cranial mesenteric artery blood flow were eliminated (38.4+/-7.6 mL/min at baseline v 36.5+/-6.8 mL/min at 90 minutes in 0 to 2 day olds; 79.9+/-10.0 mL/min at baseline v 77.5+/-14.7 mL/min in 2 week olds). Indomethacin-induced declines in renal blood flow were similarly abrogated by dopexamine.


CONCLUSIONS
Dopexamine may prove of clinical benefit when a neonate is considered a candidate for indomethacin therapy.
Mero
K A
KA
Department of Surgery, Tulane University School of Medicine, New Orleans, LA, USA.
Choe
E U
EU
Flint
L M
LM
Ferrara
J J
JJ
D000318:Adrenergic beta-Agonists / Q000494:pharmacology*; D000704:Analysis of Variance; D000818:Animals; D000831:Animals, Newborn; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000037:antagonists & inhibitors*; D004195:Disease Models, Animal; D004298:Dopamine / Q000031:analogs & derivatives* / Q000494:pharmacology; D004347:Drug Interactions; D007213:Indomethacin / Q000037:antagonists & inhibitors*; D007275:Injections, Intravenous; D011897:Random Allocation; D012016:Reference Values; D013152:Splanchnic Circulation / Q000187:drug effects*; D013552:Swine
D000318:Adrenergic beta-Agonists; D000894:Anti-Inflammatory Agents, Non-Steroidal; C046318:dopexamine; D004298:Dopamine; D007213:Indomethacin