ascorbic-acid and Placenta--Retained

Ante- and postpartum antioxidative/oxidative profiles in blood plasma of cows with and without retained placental membranes (RFM) were investigated. Twenty-two healthy pregnant cows were included in the study. Seven animals out of 22 suffered from RFM. Blood samples were obtained at 4, 3, 2, 1 weeks and 5 days antepartum (a.p.), at parturition and 1, 3, and 5 weeks postpartum. The following antioxidative parameters were measured using spectrophotometric methods: total antioxidant activity (TAC), β-carotene, vitamin A, vitamin C, and ceruloplasmin. The oxidative profile was based on the content of intermediates and end products of lipid and protein peroxidative processes which were measured by spectrophotometric and spectrofluorimetric methods. The examined parameters revealed a dynamic profile within the experimental period. The highest antioxidant and oxidant activity was noted at 2 and 1 week a.p. with a drop towards parturition suggesting the presence of oxidative stress during this time period and an apparent appropriate metabolic response of the macroorganism. Except for TAC and vitamin A, the contents of oxidative and antioxidative blood constituents did not differ between cows with and without RFM. A TAC and vitamin A by time interaction indicated higher antepartal concentrations of TAC and vitamin A in cows without RFM than in cows with RFM suggesting a possible role of antioxidative/oxidative imbalances in the aetiology of RFM.

Topics: Animals; Antioxidants; Ascorbic Acid; beta Carotene; Cattle; Ceruloplasmin; Female; Lipid Peroxidation; Oxidative Stress; Placenta, Retained; Pregnancy; Vitamin A

Vitamin C and glutathione (GSH) are water-soluble antioxidants which take part in defence mechanisms against reactive oxygen species (ROS). They may also be involved in processes of releasing/retaining bovine fetal membranes. Hence vitamin C, reduced (GSH) and oxidised (GSSG) glutathione levels were determined in retained and not-retained bovine fetal membranes in order to describe the non-enzymatic antioxidative status. Placental samples were collected immediately after spontaneous delivery or during caesarean section before term and at term, and 6 groups were formed as follows: (A) pre-term caesarean section without retained placenta; (B) pre-term caesarean section with retained placenta; (C) term caesarean section without retained placenta; (D) term caesarean section with retained placenta; (E) spontaneous delivery without retained placenta and (F) spontaneous delivery with retained placenta. Homogenates of maternal and fetal placental tissues were prepared, and vitamin C, GSH and GSSG were measured spectrophotometrically. Vitamin C levels were significantly higher in the maternal part than in the fetal part of the placenta in all groups examined. In retained placenta cases the levels were significantly lower than in control cows, except in pre-term groups. GSH concentrations were significantly higher in placentas without retention than with retention. GSSG levels showed the opposite relationship and were significantly higher in samples with retention of fetal membranes than in controls. Further experiments on antioxidative as well as oxidative status in bovine placenta are necessary.

Topics: Animals; Antioxidants; Ascorbic Acid; Cattle; Cattle Diseases; Female; Glutathione; Glutathione Disulfide; Obstetric Labor, Premature; Oxidation-Reduction; Placenta; Placenta, Retained; Pregnancy; Reactive Oxygen Species; Spectrophotometry