Following on from previous studies on dermal
inflammation in the isolated perfused bovine udder, a new in vitro model of the isolated haemoperfused bovine uterus was established for studies on acute inflammatory reactions (for example,
eicosanoid synthesis and regulation of
cyclooxygenase-1 [COX-1] and COX-2) caused by ischaemia-reperfusion (I-R) injury. The organs and blood used in this study were obtained from a slaughterhouse. Within 2 hours of slaughter, uterine perfusion was re-established, by using a mixture of homologous blood and Tyrode
solution (4:1). After equilibration, several deposits of
arachidonic acid (5 mg and 0.1 mg) and
arachidonylethanolamide (0.1 mg) were injected into the myometrial tissue. Tissue biopsies were taken from treated and untreated areas at 180 and 300 minutes after the onset of haemoperfusion, for measuring
prostaglandin E(2) (
PGE(2)) levels. In addition, the regulation of COX-1 and COX-2
mRNA was investigated by using the
reverse transcriptase-polymerase chain reaction.
Eicosanoid levels were determined by using an
enzyme immunoassay (ELISA). Because both an increase in
PGE(2) concentration and up-regulation of COX
mRNA were observed, the inhibitory effects of
dexamethasone, added to the perfusion medium, were studied.
Dexamethasone caused a significant decrease in tissue
PGE(2) production, but did not induce down-regulation of COX-2
mRNA. In conclusion, the isolated haemoperfused bovine uterus was introduced as an in vitro model of acute
inflammation, induced by I-R injury. The suitability of the model for investigating anti-inflammatory substances was demonstrated. Use of the isolated haemoperfused bovine uterus in pharmacological research and
drug screening may contribute to reducing the number of animals used for testing.