Concentrations of immunoreactive leukotriene B4 in uterine lavage fluid from mares with experimentally induced and naturally occurring endometritis.

This study investigates the levels of leukotriene B4, a chemical associated with inflammation, in mares suffering from both experimentally induced and naturally occurring endometritis. The results indicated that leukotriene B4 levels were highest when neutrophil infiltration was at its maximum, decreased to normal levels six hours post-infusion, and were not significantly affected by the administration of ovarian steroids.

Methodology and Procedure

• Endometritis, an inflammation of the uterine lining, was artificially induced in mares that had their ovaries removed. This was achieved through the infusion of a 1% solution of oyster glycogen.
• The researchers then examined the changes in concentrations of leukotriene B4, a compound that forms part of the body’s inflammatory response, in the uterine washings of these mares.

Key Findings

• The highest amounts of leukotriene B4 were found in uterine washings when the infiltration of neutrophils, a type of white blood cell, into the uterus was at its greatest.
• These leukotriene B4 concentrations then returned to base levels within six hours following the start of the infusion.
• The researchers also discovered that administering ovarian steroids to the mares did not have any significant impact on these leukotriene B4 concentrations. This suggests that ovarian steroids may not play a pivotal role in the inflammatory response associated with endometritis.

Comparison to Naturally Occurring Endometritis

• Interestingly, when the researchers compared uterine washings from mares inflicted with persistent endometritis to those from healthy mares, they did not identify any significant difference in the levels of leukotriene B4.
• This finding indicates that the presence and level of leukotriene B4 in the uterus may not be a definitive indicator of endometritis in mares.