title: Relationship between contractions of the uterus and concentration of PGF2α in uterine venous blood after luteolysis in gilts.
abstract: The origin and physiological significance of high pulses of prostaglandin F2α (PGF2α) in uterine venous blood that occur 2-3 days after luteolysis are not well understood. We studied the relationship between contractions of the uterus evoked by exogenous oxytocin (OT) and PGF2α concentration in uterine venous blood on day 17 of the porcine oestrous cycle. The infusion of OT into the uterine artery produced an immediate increase in the uterine intraluminal pressure (UIP) (p < 0.001) and a simultaneous elevation in PGF2α concentration in uterine venous blood (p < 0.0001). The infusion of indomethacin (IND) into the uterine artery slightly decreased PGF2α concentration in uterine venous blood, but it did not suppress uterine contraction or the rapid increase in PGF2α concentration in uterine venous blood just after OT infusion (p < 0.0001), which was lower that in gilts not treated with IND. We conclude that the spikes of PGF2α concentration in uterine venous blood occurring after OT infusion on day 17 of the porcine oestrous cycle are mainly caused by the excretion with venous blood from the remodelled uterus and that PGF2α synthesis may contribute to this. These results suggest that the high spikes in PGF2α concentration that occur 2-3 days after luteolysis in pigs, sheep, cows and mares all have a similar origin.
authors.affiliation: Department of Local Physiological Regulations, Institute of Animal Reproduction and Food Research of the Polish Academy of Sciences, Olsztyn, Poland.
authors.forename: S
authors.initials: S
authors.lastname: Stefańczyk-Krzymowska
authors.forename: B
authors.initials: B
authors.lastname: Wąsowska
authors.forename: P
authors.initials: P
authors.lastname: Gilun
authors.forename: J
authors.initials: J
authors.lastname: Muszak
authors.forename: W
authors.initials: W
authors.lastname: Grzegorzewski
mesh_terms: D000818:Animals; D015237:Dinoprost / Q000037:antagonists & inhibitors / Q000097:blood*; D030762:Estrous Cycle; D005260:Female; D007213:Indomethacin / Q000494:pharmacology; D007261:Infusions, Intra-Arterial; D003341:Luteolysis / Q000502:physiology*; D010121:Oxytocin / Q000008:administration & dosage; D011374:Progesterone / Q000097:blood; D034421:Sus scrofa / Q000502:physiology*; D055988:Uterine Artery / Q000187:drug effects; D014590:Uterine Contraction / Q000097:blood* / Q000187:drug effects; D014599:Uterus / Q000098:blood supply*; D014680:Veins
chemical_list: D011374:Progesterone; D010121:Oxytocin; D015237:Dinoprost; D007213:Indomethacin