Archive for the ‘Cyclooxygenase’ Category

The high concentration of COX-2 transcripts found in bovine endometrium postpartum explains the fact that plasma PGFM concentrations in parturient cows are maximal on the day after delivery. At that stage, the stimulus for COX-2 expression probably derives from cytokines released from macrophages and other cells of the immune system that invade the uterus in […]

Transportation of the cow and other procedures associated with harvesting the tissues caused a great deal of disturbance and stress for the parturient cows. Both conditions are known to interrupt the process of parturition in various species and references therein), and inhibit the release of OT. Because of its short half-life, COX-2 mRNA was probably […]

COX-1 and -2 gene expression can be regulated at both the transcriptional and the posttranscriptional levels, and species differences may exist at both levels. Transcription induced in murine or chicken embryo fibroblasts by mitogens or by oncogene-induced transformation occurs rapidly, and maximal levels are seen at 15-30 min, followed shortly by COX-2 mRNA and protein […]

The proportion of both COX-1 and COX-2 mRNA was consequently greater in total RNA from the purified COX-expressing cells than from intact endometrial tissue, and COX-1 mRNA was therefore measurable in RNA from the purified cells. An alternative explanation is that, similarly to expression of OTR gene in bovine endometrial epithelial cells, transcripts of the […]

They may also regulate COX-2 gene transcription in the maternal compartment of the bovine placenta. Directional transport of cytokines from uterine epithelial cells into underlying stromal cells to induce COX-2 expression has been demonstrated in pregnant mice. In accordance with this hypothesis, fetal cotyledons accumulated COX-2 transcripts earlier in gestation than maternal caruncles. Contamination with […]

We have demonstrated that COX-2 gene is the dominant isoform expressed in uterine tissues of advanced-pregnant cows and have provided evidence for the capacity of OT to induce expression of COX-2 mRNA in bovine endometrium in vivo. While this work was in progress, stimulation of COX-2 mRNA expression by OT in bovine endometrial cells in […]

OTChallenge Mean log normal concentrations of PGFM in the plasma of OT- and saline-injected cows are shown in Figure 4. After injection of OT, the concentration of plasma PGFM increased linearly over the 90-min experimental period (r = 0.849, p < 0.0001), whereas after saline injection, mean plasma PGFM did not increase (r = 0.154, […]

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