ABSTRACT
The aim was to evaluate effects of addition of pentoxifylline to skimmed milk semen extender on uterine inflammatory response. Thirty-six estrous cycles of 15 mares were randomly divided into five groups for artificial insemination (AI): Control: mimicking the AI procedure (nâ¯=â¯7); Extender: deposition of skimmed milk based extender (nâ¯=â¯7); Extenderâ¯+â¯PTX: skimmed milk based extender plus pentoxifylline (7.18â¯mM; n = 8); Semen: semen diluted with extender without pentoxifylline (nâ¯=â¯7), and Semenâ¯+â¯PTX: semen diluted with extender containing pentoxifylline (nâ¯=â¯7). Mares in estrus were examined by trans-rectal palpation and using ultrasonography, and ovulation was induced. Uterine hemodynamics were assessed immediately before ovulation induction (T-30), immediately before AI (T0), 2 (T2), 6 (T6), 12 (T12), 24 (T24) and 48 (T48) h after AI. Endometrial samples were collected 6â¯h after AI, and slides were stained and examined to determine percentage of PMN. Pentoxifylline had no additional effect on vascular perfusion. There was a major inflammatory response with pentoxifylline treatment that was greater than that of the control group. In the group treated with Extenderâ¯+â¯PTX, there were more PMN (57.98⯱â¯9.42%) than in the group treated with Extender (20.20⯱â¯6.63%) and in the Semenâ¯+â¯PTX group more PMN (82.84⯱â¯5.71%) than in the Semen-treated group (47.83⯱â¯10.61%). These findings indicate the addition of pentoxifylline does not stimulate blood flow; however, it induces a greater immune defense response because more neutrophils migrate to the uterine lumen.