Immunolocalization of Progesterone Receptors in Bovine Placentomes Throughout Mid and Late Gestation and at Parturition1

Schuler, Gerhard; Wirth, C; Klisch, Karl; Pfarrer, Christiane; Leiser, Rudolf; Hoffmann, Bernd

doi:10.1095/biolreprod61.3.797

Cited by 30 publications

(26 citation statements)

References 27 publications

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“…As previously described (Schuler et al 1999), PR were immunolocalized solely in cells of the caruncular stroma. There was a significant effect for the group (PZ0.0376) and subsequent pair-wise comparisons showed that the percentage of PR-positive cells in caruncles was significantly (PZ0.05) lower in the PG group compared with D272 controls (Table 2).…”

Section: Initiation Of Parturition In Cattlementioning

confidence: 96%

“…Immunohistochemical detection of COX2, CYP17, PR, GR, and the pan-leucocyte marker CD45 and evaluation of immunostaining Sections prepared from formalin-fixed paraffin-embedded placentomal tissue samples were immunostained following an indirect immunoperoxidase standard procedure including microwave irradiation for unmasking epitopes and the streptavidin-biotin technique for signal enhancement as previously described (Schuler et al 1999(Schuler et al , 2006a(Schuler et al , 2006b). Primary antibodies used were the following: a rabbit mAb against a synthetic peptide from the C-terminus of rat COX2 (Thermo Fisher Scientific, Fremont, CA, USA), a polyclonal rabbit antiserum against recombinant bovine CYP17 (gift from Prof. A Conley, UC Davis; reference: Peterson et al 2001), a monoclonal murine antibody against the highly conserved C-terminus of PR (clone 10A9; Immunotech, Hamburg, Germany), a polyclonal rabbit IgG antibody against amino acids 346-367 of human glucocorticoid receptor (PA1-511A; Affinity BioReagents, Golden, CO, USA), and a murine mAb against bovine CD45 (MCA832S; AbD Serotec, Dü sseldorf, Germany).…”

Section: Investigations Into Placentomal Histomorphologymentioning

confidence: 99%

“…For quantification of PR expression, the percentage of PR-positive cells in the caruncular stroma was determined as previously described (Schuler et al 1999) based on the evaluation of 500 cells. For COX2 and CYP17, cytoplasmic staining in UTC was evaluated using an IRS taking into account the proportions of negatively, weakly, moderately, intensely staining cells as previously described (Khatri et al 2011), which may range from 0 (all cells under investigation negative) to 10 (all cells under investigation intensely positive).…”

Section: Investigations Into Placentomal Histomorphologymentioning

confidence: 99%

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Investigations into the mechanisms controlling parturition in cattle

Shenavai

Preissing²,

Hoffmann³

et al. 2012

Reproduction

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A pronounced increase in fetal cortisol concentrations stimulating an increase in estrogen production at the expense of progesterone precursors in the placenta, luteolysis, and progesterone withdrawal is considered as a key event during the complex signal cascade leading to the initiation of parturition in cattle. However, there are many questions concerning the exact functional and/or temporal relationships between these individual processes which finally result in the expulsion of the calf and the timely release of the placenta. Thus, parturition was induced in 270-day pregnant cows using the progesterone receptor blocker aglepristone (group AG, nZ3), the prostaglandin F 2a analog cloprostenol (group PG, nZ4), and the glucocorticoid dexamethasone (group GC, nZ4) to characterize the effect on maternal steroid and prostaglandin levels and to identify immediate subsequent changes in placental morphology and gene expression as compared with untreated controls sampled on day 272 (group D272, nZ3) and cows during normal parturition (group NT, nZ4). All calves of the treatment groups were born on days 271-272, whereas gestational length in NT cows was 280.5G1.3 days. However, none of the treatments significantly induced the prepartal remodeling of placentomes characterized by a decline in trophoblast giant cells and reduction of the caruncular epithelium. Data on placental CYP17 and COX2 expression confirm that these key enzymes are upregulated by GC, whereas placental aromatase expression was not affected by any treatment. Maternal progesterone and prostaglandin profiles suggest differential effects of the treatments on luteal function and placental or uterine prostaglandin production. The results provide new information on the initiation of parturition in cattle but raise many new questions.

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Section: Initiation Of Parturition In Cattlementioning

confidence: 96%

Section: Investigations Into Placentomal Histomorphologymentioning

confidence: 99%

Section: Investigations Into Placentomal Histomorphologymentioning

confidence: 99%

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Investigations into the mechanisms controlling parturition in cattle

Shenavai

Preissing²,

Hoffmann³

et al. 2012

Reproduction

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“…In cattle, our preceding studies suggest a particular role of placental progesterone and oestrone as local regulators of placental growth and differentiation (Hoffmann et al 1997, Schuler et al 1999, 2005, Hoffmann & Schuler 2002. Sites of placental steroid production are the fetal cotyledons (Hoffmann et al 1979, Conley & Ford 1987, Schuler et al 1994 which, together with the maternal caruncular tissue, form multiple discrete sites of placentation, the placentomes (Leiser & Kaufmann 1994).…”

Section: Introductionmentioning

confidence: 99%

“…In contrast, the bovine trophoblast has been shown to express all enzyme activities necessary for the conversion of pregnenolone into oestrone (Schuler et al 1994). However, no definitive information is available on the steroidogenic capacity of the two morphologically distinct cell types forming the bovine trophoblast, the uninucleated trophoblast cells (UTCs) and the generally binucleated trophoblast giant cells (TGCs) (Wooding & Wathes 1980, Klisch et al 1999.…”

Section: Introductionmentioning

confidence: 99%

Reciprocal expression of 17α-hydroxylase-C17,20-lyase and aromatase cytochrome P450 during bovine trophoblast differentiation: a two-cell system drives placental oestrogen synthesis

Schuler¹,

Özalp²,

Hoffmann³

et al. 2006

Reproduction

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No definitive information is yet available on the steroidogenic capacity of the two morphologically distinct cell types forming the bovine trophoblast, the uninucleated trophoblast cells (UTCs) and the trophoblast giant cells (TGCs). Hence, in order to localise 17a-hydroxylase-C17,20-lyase (P450c17) on a cellular level and to monitor its expression as a function of gestational age, placentomes from pregnant (days 80 -284; n 5 19), prepartal (days 273 -282; 24 -36 h prior to the onset of labour; n 5 3) and parturient cows (n 5 5) were immunostained for P450c17 using an antiserum against the recombinant bovine enzyme. At all stages investigated, P450c17 was exclusively found in the UTCs of chorionic villi (CV), where staining was ubiquitous between days 80 and 160, but was largely restricted to primary CV and the branching sites of secondary CV between days 160 and 240. Thereafter, a distinct ubiquitous staining reoccurred in the UTCs of all CV in late pregnant, prepartal and parturient animals. Using an antiserum against human aromatase cytochrome P450 (P450arom), specific cytoplasmic staining was observed in TGCs. In placentomes from pregnant cows, staining intensity was higher in mature compared with immature TGCs and was more pronounced in the trophoblast covering big stem villi compared with the trophoblast at other sites of the villous tree. In placentomes of a parturient cow, specific staining was only found in mature TGCs that survived the normal, but substantial, prepartal decline in TGC numbers. These results clearly showed that bovine UTCs and TGCs exhibit different steroidogenic capacities, constituting a 'two-cell' organisation for oestrogen synthesis. P450c17 expression appears to be quickly down-regulated and P450arom is up-regulated when UTCs enter the TGC differentiation pathway.

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Multilevel regulation of steroid synthesis and metabolism in the bovine placenta

Nguyen

Conley

Soboleva

et al. 2012

Molecular Reproduction Devel

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SUMMARYSteroid hormones play critical roles in almost all physiological processes in male and female reproduction. In a normal pregnancy, the concentrations of steroid hormones in maternal and foetal blood vary with gestation in response to changing needs. The placenta plays a central role in producing the appropriate steroids to support the pregnancy by coordinating its own steroidogenic activity with that of the corpus luteum and responding to foetal signals. Although much is known about the steroidogenic potential of the bovine placenta, far less is known about how the placenta integrates the synthesis of steroids with their subsequent metabolism and clearance to achieve appropriate local and peripheral concentrations of steroids in maternal and foetal blood at each stage of gestation. This review focuses on the current knowledge of the temporal and spatial regulation and compartmentalization of the biochemical pathways by which potent steroid hormones are synthesized and metabolized in the bovine placenta. The aim is to increase our understanding of how the balance of synthesis and metabolism determines placental steroid output as it changes with development and differentiation, and how this is regulated in response to the variations in the foetal signals and luteal secretory activity. The review highlights knowledge gaps and suggests that mathematical modelling can help understand the effect of different levels of regulation on the steroidogenic output of an organ, such as the bovine placenta.

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Immunolocalization of Progesterone Receptors in Bovine Placentomes Throughout Mid and Late Gestation and at Parturition1

Cited by 30 publications

References 27 publications

Investigations into the mechanisms controlling parturition in cattle

Investigations into the mechanisms controlling parturition in cattle

Reciprocal expression of 17α-hydroxylase-C17,20-lyase and aromatase cytochrome P450 during bovine trophoblast differentiation: a two-cell system drives placental oestrogen synthesis

Multilevel regulation of steroid synthesis and metabolism in the bovine placenta

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