288. The post-insemination inflammatory response in the ewe
J. L. Scott A , N. Ketheesan A and P. M. Summers ASchool of Veterinary and Biomedial Sciences, James Cook University, Townsville, QLD, Australia
Reproduction, Fertility and Development 17(9) 121-121 https://doi.org/10.1071/SRB05Abs288
Submitted: 26 July 2005 Accepted: 26 July 2005 Published: 5 September 2005
Abstract
Insemination causes an inflammatory response in the female reproductive tract of many species. The cytokine/leukocyte network initiated during this reaction is believed to enhance reproductive success.1 This study investigated the post-insemination inflammatory response in the ewe. Fifteen nonparous ewes were mated with the same ram for 1 h and their reproductive tracts were collected 3, 6, 18, 24 or 48 h later. Another fifteen ewes were used as controls. Tissue samples and luminal mucus were collected from 10 sites in each reproductive tract and stained with haematoxylin and eosin, Diffquik and immunohistochemically using a monoclonal CD68 antibody to quantify neutrophils, eosinophils and macrophages. Presence of interleukin-8 (IL-8) and granulocyte-macrophage colony-stimulating factor (GM-CSF) was investigated using immunohistochemistry and enzyme-linked immunosorbent assay. Neutrophils and macrophages increased in reproductive tissues following insemination. Mean cell counts in 1.5-mm2 tissue of mated (M) and control (C) ewes demonstrated a peak in neutrophils at 6–18 h post-insemination with significant differences (P < 0.05) between mated and controls in the posterior cervix (M = 23.7; C = 4.1) and uterine body (M = 34.5; C = 11.5). Macrophages peaked at 18–24 h with significant differences (P < 0.05) between mated and controls in the vagina (M = 13.4; C = 4.6), posterior cervix (M = 10.4; C = 2.7), mid-cervix (M = 8.5; C = 3.0) and ipsilateral mid-uterine horn (M = 14.2; C = 7.9). Neutrophils increased in the lumen of the cervix and uterine body following insemination but macrophage numbers did not change. Insemination did not affect eosinophils. IL-8 and GM-CSF were detected in endometrial epithelial cells in mated and non-mated ewes. Highest concentrations of IL-8 were found in vaginal mucus. Small quantities of GM-CSF were detected in occasional mucus samples. No difference between mated and non-mated ewes was demonstrated for either cytokine. In conclusion, the post-insemination inflammatory reaction in the ewe involves an increase in neutrophils and macrophages in reproductive tissues, with neutrophils crossing the epithelium into the lumen. There was no apparent increase in IL-8 or GM-CSF in response to insemination.
(1) Robertson SA et al. (1997) American Journal of Reproductive Immunology 37, 438–442.
