Leukotrienes (LTs) are important as pro-inflammatory mediators to the innate immune response,
inflammation, and
allergy. Although it is known that
inflammation of the uterus in gilts leads to an increase in
LTB4 and
LTC4 synthesis, researchers lack knowledge regarding the expression of LT receptors in the inflamed uterus. The aim of this experiment was to determine the levels of cysteinyl LT receptors type 1 (CysLT(1)R) and type 2 (CysLT(2)R), as well as of
LTB4 receptor type 1 (LTB4R1)
mRNA and
protein expression, and the cellular localization of these receptors in the inflamed porcine uterus. On Day 3 of the estrous cycle (Day 0 of the study), 50 ml of either saline or Escherichia coli
suspension (109 colony-forming units/ml) was injected into each uterine horn.
Injections of bacteria increased CysLT(1)R
mRNA levels in the endometrium on Days 8 and 16 of the study and in the myometrium on Day 16, as well as the CysLT(1)R
protein level in the endometrium on Day 8. In the inflamed uteri, CysLT(2)R
mRNA levels in the myometrium were increased on Days 8 and 16; however, the
protein levels of this receptor decreased in the endometrium (Day 16) and myometrium (Day 8). After bacterial treatment, LTB4R1
mRNA and
protein levels in the endometrium on Day 8, and LTB4R1
mRNA levels in the myometrium on Days 8 and 16 were found to have increased. Data obtained show that
inflammation of porcine uteri changes the expression of LT receptors, suggesting their importance in the course/consequences of uterine
inflammation.