Dynamics of lipid droplets in the endometrium and fatty acids and oxylipins in the uterine lumen, blood, and milk of lactating cows during diestrus

Our objective was to investigate the lipid content of uterus, blood plasma, and milk at early, mid, late diestrus. Lactating cows (n = 30) had estrous cycle ovulation synchronized by administration exogenous hormones. Cows were blocked parity assigned randomly receive transcervical uterine flushing biopsy on d 5 (early diestrus), 10 (mid diestrus) or 15 (late cycle. Flushing endometrial performed in horn ipsilateral corpus luteum. The recovered used for analyses composition liquid chromatography-tandem mass spectrometry investigation droplet abundance cryosections using a neutral fluorescent dye. In addition, samples collected from all 5, 10, 15. All measure concentration progesterone determine composition. Subsamples plasma also evaluate fatty acids oxylipins same methodology samples. droplets endometrium increased 1.9-fold 2-fold Concentration long-chain were, average, 2.2 2.5 times greater compared with those 10. These differences not observed milk, suggesting that accumulation uterus is regulated locally. addition concentration, profile individual lumen changed substantially during main categories diestrus mono- polyunsaturated acids, derived arachidonic acid, dihomo-γ-linolenic docosahexaenoic acid. conclusion, accumulate might work as mechanism supply these lipids developing conceptus diestrus, when onset elongation occurs substantial synthesis biomass cell signaling mediators are required.