ACTIVITY OF STEROID C-17,20 LYASE IN THE OVINE PLACENTA: EFFECT OF EXPOSURE TO FOETAL GLUCOCORTICOID

1976 ◽  
Vol 69 (2) ◽  
pp. 239-246 ◽  
Author(s):  
PENELOPE A. STEELE ◽  
A. P. F. FLINT ◽  
A. C. TURNBULL
Keyword(s):  
Post Partum ◽  
Late Pregnancy ◽  
Peripheral Circulation ◽  
Ovine Placenta ◽  
Spontaneous Onset

SUMMARY Microsomal fractions isolated from post-partum ovine placentae catalysed the synthesis of [3H]oestrone and [3H]oestradiol from [3H]17α-hydroxyprogesterone and NADPH; oestrone and oestradiol were formed in a ratio of approximately 50:1. The expected intermediate, [3H]androstenedione, did not accumulate during these incubations but was shown by trapping experiments to be the intermediate involved. Mean ( ± s.d.) yields of [3H]oestrone (% conversion of substrate) during incubation for 1 h of placentae from five animals in late pregnancy before the onset of labour, from five animals which delivered spontaneously at term and from four animals in which labour was induced by administration of dexamethasone to the foetus were: in tissue obtained before labour, 3·2 ± 0·44; in tissue obtained after the spontaneous onset of labour, 20·6 ± 10·2 (P < 0·01) and in tissue obtained after dexamethasone-induced labour, 24·4 ± 2·13 (P < 0·001). This increase in oestrone synthesis suggests activation of steroid C-17,20 lyase, since this is the step limiting the rate of synthesis of oestrone in vitro. The enzyme is probably activated by foetal glucocorticoid. The findings are discussed in relation to the site of synthesis of oestrogens which in the sheep increase in concentration in the peripheral circulation at term, and with reference to a possible mechanism by which foetal glucocorticoid may control the onset of labour in this species.

INCREASE IN THE RESPONSE TO ADRENOCORTICOTROPHIN OF ISOLATED MATERNAL ADRENAL CELLS FROM SHEEP IN LATE PREGNANCY

1980 ◽  
Vol 86 (1) ◽  
pp. 93-100 ◽  
Author(s):  
J. A. GLICKMAN ◽  
J. E. PATRICK ◽  
J. R. G. CHALLIS
Keyword(s):  
Early Pregnancy ◽  
Post Partum ◽  
Late Pregnancy ◽  
Maximum Output ◽  
Maximal Concentration ◽  
Adrenal Cells ◽  
Melanocyte Stimulating Hormone ◽  
Pregnant Sheep ◽  
The Absolute

Adrenal cells were prepared from non-pregnant (anoestrous) sheep, from ewes at days 50, 100 and 130 of pregnancy and at term, and from animals at 1–5 days post partum. The ability of the cells to respond to adrenocorticotrophin (ACTH1–24), α-melanocyte-stimulating hormone (α-MSH), or combinations of these peptides has been examined in vitro. There was a progressive rise in the basal output of cortisol during pregnancy and in the absence of adrenocorticotrophin the cortisol output from adrenal cells of late pregnant and post-partum sheep was significantly greater than that from the non-pregnant animals. Adrenocorticotrophin increased cortisol output by adrenal cells at all times tested. In anoestrous sheep the amount of ACTH required to produce half the maximum output of steroid (ED50) was 8 pg/ml. The ED50 increased in early pregnancy to 112 pg/ml and then fell to < 5 pg/ml between day 100 and term. At term both the stimulation ratio and the absolute increment in cortisol output elicited by a maximal concentration of ACTH were greater than at any other time tested in pregnant or non-pregnant sheep. Cortisol output during pregnancy was not increased by α-MSH, although at term the stimulatory effect of ACTH1–24 was partially antagonized by α-MSH. These results suggest that there may be an increase in the responsiveness of the maternal adrenal during pregnancy, although the factor(s) responsible remains unknown.

PLACENTAL PRODUCTION OF 5β-PREGNANE-3α,20α-DIOL IN GOATS

1981 ◽  
Vol 90 (2) ◽  
pp. 151-158 ◽  
Author(s):  
E. L. SHELDRICK ◽  
A. P. RICKETTS ◽  
A. P. F. FLINT
Keyword(s):  
Medroxyprogesterone Acetate ◽  
Plasma Concentrations ◽  
Placental Tissue ◽  
Late Pregnancy ◽  
Repeated Administration ◽  
Peripheral Circulation ◽  
Major Product ◽  
Progesterone Metabolism ◽  
Reductive Metabolism

A major product of progesterone metabolism by the goat placenta in vitro was found to be 5β-pregnane-3α,20α-diol. The concentration of this steroid has been measured by radioimmunoassay in the peripheral circulation during pregnancy. Peripheral plasma concentrations of 5β-pregnane-3α,20α-diol were low (less than 6 nmol/l) in anoestrous and non-pregnant ovariectomized goats, and during the first month of pregnancy but increased progressively after day 45 of pregnancy, reaching 78–94 nmol/l between days 112 and 142. Thereafter levels declined before term. Changes in the plasma concentration of 5β-pregnane-3α,20α-diol during pregnancy in the goat therefore resembled those of progesterone in the sheep. Plasma concentrations of 5β-pregnane-3α,20α-diol between day 70 and term were not influenced by repeated administration of medroxyprogesterone acetate from days 51 to 82 or by lutectomy in goats treated with medroxyprogesterone acetate. Secretion of 5β-pregnane-3α,20α-diol by the uterus and its contents was indicated by a positive venous–arterial difference across the uterus between days 128 and 141 in three ovariectomized pregnant goats receiving medroxyprogesterone acetate. Comparison of the rates of metabolism of progesterone by homogenates of placenta in vitro showed that the placental tissue from goats was three times more active in this respect than was tissue from sheep. The ratio of the plasma concentrations of 5β-pregnane-3α,20α-diol and progesterone in late pregnancy in ovariectomized or lutectomized goats exceeded by a factor of 10 that in sheep at a comparable stage of gestation. It is suggested that reductive metabolism of progesterone before it is secreted may account for the inability of the placenta to maintain pregnancy after ovariectomy in goats.

scholarly journals Antigen-Specific Immunoglobulin A Antibodies Secreted from Circulating B Cells Are an Effective Marker for Recent Local Immune Responses in Patients with Cholera: Comparison to Antibody-Secreting Cell Responses and Other Immunological Markers

2003 ◽  
Vol 71 (8) ◽  
pp. 4808-4814 ◽  
Author(s):  
Firdausi Qadri ◽  
Edward T. Ryan ◽  
A. S. G. Faruque ◽  
Firoz Ahmed ◽  
Ashraful Islam Khan ◽  
...  
Keyword(s):  
Immune Responses ◽  
Immunoglobulin A ◽  
Peripheral Circulation ◽  
Secreting Cell ◽  
Antibody Secreting Cell ◽  
Immunological Responses ◽  
B Subunit ◽  
Mucosal Infection ◽  
Circulating Lymphocytes

ABSTRACT Gut-derived lymphocytes transiently migrate through the peripheral circulation before homing back to mucosal sites and can be detected using an ELISPOT-based antibody secreting cell (ASC) assay. Alternatively, transiently circulating lymphocytes may be cultured in vitro, and culture supernatants may be assayed for antigen-specific responses (antibody in lymphocyte supernatant [ALS] assay). The ALS assay has not been validated extensively in natural mucosal infection, nor has the ALS response been compared to the ASC assay and other cholera-specific immunological responses. Accordingly, we examined immune responses in 30 adult patients with acute cholera in Bangladesh, compared with 10 healthy controls, measuring ALS-immunoglobulin A (IgA), ASC-IgA, and serum and fecal IgA responses to two potent Vibrio cholerae immunogens, the nontoxic B subunit of cholera toxin (CtxB) and lipopolysaccharide (LPS) and a weaker V. cholerae immunogen, the mannose-sensitive hemagglutinin (MSHA). We found significant increases of anti-CtxB, anti-LPS, and anti-MSHA IgA in supernatants of lymphocytes cultured 7 days after onset of cholera using the ALS assay. We found that ALS and ASC responses correlated extremely well; both had comparable sensitivities as the vibriocidal responses, and both procedures were more sensitive than fecal IgA measurements. An advantage of the ALS assay for studying mucosal immune responses is the ability to freeze antibodies in supernatants for subsequent evaluation; like the ASC assay, the ALS assay can distinguish recent from remote mucosal infection, a distinction that may be difficult to make in endemic settings using other procedures.

The effect of ammonia treatment on the intake of straw and hay when offered with rations of concentrates to ewes in late pregnancy

1985 ◽  
Vol 40 (1) ◽  
pp. 101-109 ◽  
Author(s):  
R. J. Orr ◽  
T. T. Treacher ◽  
V. C. Mason
Keyword(s):  
Organic Matter ◽  
Body Condition Score ◽  
Spring Barley ◽  
Live Weight ◽  
Late Pregnancy ◽  
Barley Straw ◽  
Ammonia Treatment ◽  
Condition Score ◽  
Forage Intake

ABSTRACTFinnish Landrace × Dorset Horn ewes were offered 300, 600 or 900 g fresh weight per day of concentrates and forage ad libitum from day 105 of pregnancy until lambing. Spring barley straw (S) or hay (H) was offered either untreated (U) or following treatment with anhydrous ammonia in an oven (T). Organic matter digestibilities (in vitro) were 0·42, 0·58, 0·42 and 0·60 and nitrogen contents were 7·2, 18·6, 12·0 and 25·0 g/kg dry matter for US, TS, UH and TH respectively. Forage intake did not differ between ewes carrying two or more foetuses but the small number of ewes carrying one foetus ate more straw (6·8 v. 4·5 g organic matter (OM) per kg live weight) than ewes carrying two or more foetuses. Ammonia treatment increased intake; the increase was larger on straw (4·6 v. 100 g OM per kg live weight) than on hay (9·0 v. 10·7 g OM per kg live weight). Replacement rates of forage by concentrates were -0·21, +0·06, -0·48 and +0·08 kg forage per kg concentrates for treatments US, TS, UH and TH respectively; only the value for treatment UH differed significantly from zero. On most treatments forage intake decreased as pregnancy progressed and the declines were greater when treated forages were offered. Concentrate level had a large effect on most aspects of ewe performance. Ewes offered treated forage gained slightly more weight in pregnancy (138 v. 104 g/day), had a slightly smaller decrease in body condition score (-0·54 v. -0·68) between day 105 and lambing but did not have greater lamb birth weights than ewes on untreated forage.

Inhibition of binding of gonadal steroids to serum binding proteins by non-esterified fatty acids: the influence of chain length and degree of unsaturation

1989 ◽  
Vol 120 (2) ◽  
pp. 175-179 ◽  
Author(s):  
C. Street ◽  
R. J. S. Howell ◽  
L. Perry ◽  
S. Al-Othman ◽  
T. Chard
Keyword(s):  
Fatty Acids ◽  
Protein Binding ◽  
Unsaturated Fatty Acids ◽  
Late Pregnancy ◽  
Sex Hormone Binding Globulin ◽  
Partial Purification ◽  
Normal Female ◽  
Esterified Fatty Acids ◽  
Vitro Binding

Abstract. The effect of non-esterified fatty acids (NEFA) on the in vitro binding of testosterone, 5-alpha dihydrotestosterone and estradiol E2 to sex hormone binding globulin (SHBG) was examined using pooled normal female serum, and SHBG and albumin fractions obtained from the partial purification of late pregnancy serum. A range of saturated and unsaturated fatty acids were examined for their effect on steroid-protein binding. In normal female serum, NEFA added at physiological concentrations disrupted steroid-protein binding. The shorter chain (C8–C12) saturated acids and the poly-unsaturated acids proved to be more effective inhibitors than the longer chain saturated or mono-unsaturated acids. The greatest inhibition was obtained with E2 whereas the binding of dihydrotestosterone was least affected. With partially purified SHBG, the same concentrations of NEFA were less effective at inhibiting the binding of dihydrotestosterone and testosterone but elicited the same effect with E2. The binding of steroids to albumin appeared to be unaffected by these concentrations of NEFA.

Kisspeptin/Kiss1r system and angiogenic and immunological mediators at the maternal-fetal interface of domestic cats

2021 ◽  
Author(s):  
Luciano Cardoso Santos ◽  
Jeane Martinha dos Anjos Cordeiro ◽  
Larissa da Silva Santana ◽  
Bianca Reis Santos ◽  
Erikles Macêdo Barbosa ◽  
...  
Keyword(s):  
Gene Expression ◽  
Late Pregnancy ◽  
Domestic Cats ◽  
Placental Angiogenesis ◽  
Spatiotemporal Expression ◽  
Gene Correlation ◽  
Lh Release ◽  
Gonadotrophin Releasing Hormone ◽  
Maternal Fetal Interface

Abstract The Kisspeptin/Kiss1r system is a key regulator of reproduction by stimulating gonadotrophin-releasing hormone (GnRH) and luteinizing hormone (LH) release, and in vitro studies have shown that Kisspeptin can modulate angiogenesis and immune function, factors that are also essential for reproduction However, there are no studies on the expression of Kisspeptin/Kiss1r at the maternal-fetal interface in domestic cats and its relationship with angiogenic and immunological mediators. Thus, our objective was to evaluate the spatiotemporal expression profile of Kisspeptin/Kiss1r and angiogenic and immunological mediators in the uterus and placenta of domestic cats during pregnancy. Uterus and placenta samples were collected from cats in mid pregnancy (N = 6) and late pregnancy (N = 6), in addition to uterus from non-pregnant cats in diestrus (N = 7), to evaluate protein and gene expression of Kiss1, Kiss1r, VEGF, Flk-1, PLGF, INFγ, MIF, TNFα, IL6, and IL10 by immunohistochemistry and qPCR. Pregnancy increased the uterine expression of Kiss1 and Kiss1r, especially at the late pregnancy, in addition to upregulating INFy, MIF, Vegf, Il10, and Tnf and downregulating Plgf. Higher placental expression of Kiss1r and Plgf mRNA occurred at the late pregnancy, while the expression of Kiss1, VEGF, Flk-1, INFy, TNFα, Il6, and IL10 was higher in the mid of pregnancy. A positive correlation between Kiss1 and Tnf was observed in the placenta, while Kiss1r had a negative correlation with Infγ, Il6, and Il10. The findings reveal that Kisspeptin/Kiss1r and angiogenic and immunological mediators at the maternal-fetal interface of pregnant cat have a gene correlation and are modulated by the gestational age. These data suggest possible functional links of Kisspeptin in placental angiogenesis and immunology.

The effect of level and pattern of energy intake during late pregnancy on the performance of housed Scottish Blackface ewes

1973 ◽  
Vol 16 (2) ◽  
pp. 165-171 ◽  
Author(s):  
T. H. McClelland ◽  
T. J. Forbes
Keyword(s):  
Body Weight ◽  
Energy Intake ◽  
Post Partum ◽  
Body Weight Loss ◽  
Late Pregnancy ◽  
High Energy ◽  
Metabolizable Energy ◽  
Feeding Period ◽  
Total Period ◽  
Constant Energy

SUMMARYSixty Scottish Blackface ewes were used in a 2 × 2 factorial experiment in which two levels of metabolizable energy (ME) were given during the final 6 weeks of pregnancy. In two treatments 1600 and 2000 kcal M E were given daily over the total period while in the remaining treatments daily ME intakes were 1200 and 1600 kcal ME during the first 3 weeks of the feeding period and 2000 and 2400 kcal ME during the last 3 weeks. Digestible crude protein (DCP) intakes were constant at approximately 30 g per head daily in the constant energy treatments and 15 and 45 g per head daily in the first and second periods respectively for the low-high energy treatments.Energy intake had no statistically significant effect on lamb birth weight nor on ewe net body-weight change (change from the start of the experimental feeding period to immediately post partum). Ewes on low-high energy intakes had a significantly lower net body-weight loss than did ewes on constant energy intakes. Pattern of feeding had no significant effect on lamb birth weights. Negative nitrogen balances were found during the first feeding period where the daily DCP intake was approximately 15 g per head.

scholarly journals Ligilactobacillus salivarius PS2 Supplementation during Pregnancy and Lactation Prevents Mastitis: A Randomised Controlled Trial

2021 ◽  
Vol 9 (9) ◽  
pp. 1933
Author(s):  
Esther Jiménez ◽  
Susana Manzano ◽  
Dietmar Schlembach ◽  
Krzysztof Arciszewski ◽  
Rocio Martin ◽  
...  
Keyword(s):  
Placebo Group ◽  
Post Partum ◽  
Controlled Trial ◽  
Late Pregnancy ◽  
Probiotic Strain ◽  
Study Groups ◽  
Rank Test ◽  
Double Blind ◽  
Pregnancy And Lactation ◽  
Randomised Controlled

Mastitis is considered one of the main reasons for unwanted breastfeeding cessation. This study aimed to investigate the preventive effect of the probiotic strain Ligilactobacillus salivarius PS2 on the occurrence of mastitis in lactating women. In this multicountry, multicenter, randomized, double-blind, placebo-controlled trial, 328 women were assigned to the probiotic or the placebo group. The intervention started from the 35th week of pregnancy until week 12 post-partum. The primary outcome was the incidence (hazard) rate of mastitis, defined as the presence of at least two of the following symptoms: breast pain, breast erythema, breast engorgement not relieved by breastfeeding, and temperature > 38 °C. The probability of being free of mastitis during the study was higher in the probiotic than in the placebo group (p = 0.022, Kaplan–Meier log rank test) with 9 mastitis cases (6%) vs. 20 mastitis cases (14%), respectively. The hazard ratio of the incidence of mastitis between both study groups was 0.41 (0.190–0.915; p = 0.029), indicating that women in the probiotic group were 58% less likely to experience mastitis. In conclusion, supplementation of L. salivarius PS2 during late pregnancy and early lactation was safe and effective in preventing mastitis, which is one of the main barriers for continuing breastfeeding.

Oxytocin receptor concentrations, inositol phosphate turnover and prostaglandin release by endometrium from ewes induced to ovulate during the early post-partum period

1993 ◽  
Vol 136 (1) ◽  
pp. 17-NP ◽  
Author(s):  
J. M. Wallace ◽  
M. G. Thompson ◽  
R. P. Aitken ◽  
M. A. Cheyne
Keyword(s):  
Receptor Binding ◽  
Inositol Phosphate ◽  
Post Partum ◽  
Oxytocin Receptor ◽  
Receptor Expression ◽  
Luteal Function ◽  
Induction Of Ovulation ◽  
Release Device ◽  
Prostaglandin F

ABSTRACT Induction of ovulation early post partum in sheep is associated with a high incidence (30–40%) of premature luteolysis. The present study was designed to characterize oxytocin receptor levels, oxytocin-stimulated inositol phosphate (IP) turnover (second messenger) and oxytocin-stimulated prostaglandin F2α (PGF2α) release in the endometrium of post-partum ewes induced to ovulate 21 days after parturition and expected to exhibit a range of corpus luteal functions subsequently. Ovulation was induced on day 21 post partum using a controlled internal drug release device and pregnant mare serum gonadotrophin, and uterine tissues were collected on days 5, 10 or 15 of the cycle (n = 4/day). A further 12 ewes whose interval from previous parturition exceeded 150 days were similarly treated and acted as controls. Measurement of daily peripheral progesterone concentrations revealed that while all control ewes exhibited normal luteal function, abnormal luteal function was evident in two, two and one post-partum ewes studied on days 5, 10 and 15 of the cycle respectively. Oxytocin receptor binding was detected (by receptor-binding assay and in-vitro autoradiography) in the endometrium and myometrium of post-partum ewes at all three stages of the oestrous cycle but only at day 15 in control ewes. To determine IP turnover, 100 mg caruncular endometrium was incubated in duplicate for 2·5 h with 10 μCi [3H]inositol and treated with 0 or 2 μmol oxytocin/l for 30 min, then [3H]inositol mono-, bis- and trisphosphates were quantified. Oxytocin stimulated total IPs in all day-5 and day-15 post-partum ewes, in three of four day-10 ewes and in all day-15 control ewes. Basal endometrial PGF2α release measured in triplicate (100 mg/well) during a 2 h incubation was higher in post-partum versus control ewes on days 5 and 10 but not on day 15 of the cycle. Similarly, oxytocin stimulated PGF2α release to varying levels at all stages of the cycle in post-partum ewes but only on day 15 in control ewes. Irrespective of the treatment group endometrial oxytocin receptor number was significantly (P < 0·001) correlated with oxytocin-stimulated IP turnover and PGF2α release. Thus the induction of ovulation and the subsequent luteal phase in post-partum ewes is against a back ground of high oxytocin receptor expression and enhanced PGF2α release which in some ewes may contribute to abnormal luteal function. Journal of Endocrinology (1993) 136, 17–25

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