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1.
The ochratoxin A (OTA) content of urine samples from 88 healthy humans living at five settlements in three counties of Hungary was determined by immunoaffinity column cleanup and high-performance liquid chromatography (HPLC). OTA was detected in 61% of the samples in an average concentration of 0.013 ng/ml (range: 0.006-0.065 ng/ml). OTA concentrations measured in urine samples from men and women were not significantly different. The OTA concentration of samples from Heves county was significantly (t-test; p < 0.003) higher than that of samples from Hajdú-Bihar and Somogy counties. The regional differences in OTA concentration of urine samples indicate regional differences in the OTA exposure of the human population. Further studies are necessary to determine the cause of the regional differences in the OTA intake. The studies allow us to conclude that the OTA intake of the majority of the Hungarian population is low (< 1 ng/kg of body weight per day) but a certain part of the rural population may take up higher levels of OTA.  相似文献   

2.
The role of decreased luteal activity in embryonic loss after induced endotoxemia was studied in mares 21 to 35 days pregnant. Fourteen pregnant mares were treated daily with 44 mg of altrenogest to compensate for the loss of endogenous progesterone secretion caused by prostaglandin F2 alpha (PGF2 alpha) synthesis and release following intravenous administration of Salmonella typhimurium endotoxin. Altrenogest was administered daily from the day of endotoxin injection until day 40 of gestation (group 1; n = 7), until day 70 (group 2; n = 5), or until day 50 (group 3; n = 2). In all mares, secretion of PGF2 alpha, as determined by the plasma 15-keto-13,14-dihydro-PGF2 alpha concentrations, followed a biphasic pattern, with an initial peak at 30 minutes followed by a second, larger peak at 105 minutes after endotoxin injection. Plasma progesterone concentrations decreased in all mares to values less than 1 ng/ml within 24 hours after endotoxin injection. In group 1, progesterone concentrations for all mares were less than 1 ng/ml until the final day of altrenogest treatment. In 6 of 7 mares in group 1, the fetuses died within 4 days after the end of treatment, with progesterone concentrations less than 1 ng/ml at that time. In the mare that remained pregnant after the end of treatment, plasma progesterone concentration was 1.6 ng/ml on day 41 and increased to 4.4 ng/ml on day 44. In group 2, all mares remained pregnant, even though plasma progesterone concentrations were less than 1 ng/ml in 4 of 5 mares from the day after endotoxin injection until after the end of altrenogest treatment.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

3.
We have investigated the effects of systemic administration of the oxytocin antagonist (OTA) L-368,899 on luteolytic PGF(2alpha) release in ewes. In the first study, carried out in four ovariectomized ewes primed with progesterone to induce responsiveness to oxytocin, 3-h i.v. infusions of 3, 10 and 30 microg/kg/min OTA, carried out on days 12, 14, 16 and 18 in a Latin Square design, resulted in a significant attenuation of the oxytocin induced increase in PGFM concentration at all doses (OTA 139+/-8.3% of pre-oxytocin baseline; control 206.8+/-18.7%; P<0.005). In a further study, continuous infusion of cyclic ewes (n=6) with 10 microg/kg/min OTA from day 13 to day 17 of the cycle resulted in a reduction in both the frequency (OTA 1.0+/-0.4/ewe; control 2.2+/-0.2/ewe; P<0.05) and amplitude (OTA 31.8+/-11.0 pg/ml; control 68.8+/-10.4 pg/ml; P<0.05) of endogenous PGFM episodes compared to control ewes (n=5) measured during daily 8-h sampling windows on days 14-17. This reduction in PGFM concentrations was accompanied by a modest extension in the day of luteolysis (progesterone <0.5 ng/ml) to day 17.5+/-0.4 in the OTA treated group compared with day 16.4+/-0.5 in the control group (P=0.07). The results demonstrate that treatment with OTA caused a significant reduction in episodes of increased PGFM concentration during the period of luteolysis and may provide an approach by which to reduce early pregnancy failure.  相似文献   

4.
The present studies were undertaken to examine the effect of tumour necrosis factor (TNF) alpha on prostaglandins (PGs) F(2alpha) and E(2) release by cultured porcine endometrial cells harvested on days 13-16 after oestrus in comparison to stimulation with oxytocin (OT) and luteinizing hormone (LH). A time-dependent effect of TNFalpha (10 ng/ml) on PGF(2alpha) release was observed in stromal and luminal epithelial cells. Moreover, TNFalpha increased PGF(2alpha) secretion from both endometrial cell types with effective concentrations of 1 (p < 0.05), 10 and 50 ng/ml (p < 0.01). The effect of TNFalpha (10 ng/ml) on endometrial PGF(2alpha) and PGE(2) release was compared with OT (100 nmol/l) and LH (100 ng/ml). All factors affected PGF(2alpha) secretion from stromal cells, however, the stimulation tended to be more potent after OT and LH (p < 0.01) than after TNFalpha (p < 0.05) treatment. In epithelial cells, only TNFalpha was able to stimulate PGF(2alpha) release (p < 0.001). PGE(2) secretion from stromal cells increased after incubation with TNFalpha and OT (p < 0.05). Only LH stimulated PGE(2) release from epithelium (p < 0.001), and its action was very effective when compared with TNFalpha or OT (p < 0.01). Summarizing, TNFalpha induces both PGs secretion from cultured porcine endometrium, but preferentially stimulates PGF(2alpha) release from luminal epithelial cells. Therefore, similarly to OT and LH, TNFalpha may be considered as a potential modulator of endometrial PGF(2alpha) production during luteolysis in the pig.  相似文献   

5.
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6.
This study evaluated the effect of dexamethasone on endotoxin-induced production of tumor necrosis factor (TNF) activity in vitro by equine peritoneal macrophages. Peritoneal macrophages from adult horses were cultured in the presence of dexamethasone (1-100 microM) for various time periods (2 hour, 0.5 hour, 0 hour) prior to the addition of endotoxin (5 ng/ml), then the secretion of TNF activity was evaluated. Macrophage supernatant concentrations of TNF activity were estimated by a modified in vitro cytotoxicity bioassay using the murine fibrosarcoma cell line, WEHI 164 clone 13. An experiment was performed to determine whether dexamethasone interfered with the cytolytic bioassay's ability to detect TNF activity. The endotoxin-induced TNF activity production by equine peritoneal macrophages was significantly reduced by co-incubation with 100 microM dexamethasone, but not by tested concentrations of dexamethasone less than 100 microM. This concentration of dexamethasone greatly exceeds those generally attained by therapeutic use of dexamethasone in horses. Preincubation time did not affect the ability of 100 microM dexamethasone to reduce TNF production by equine macrophages. The quantitation of equine TNF activity by its cytolytic bioassay was not altered by dexamethasone.  相似文献   

7.
Regulation of ovine alveolar macrophage function by recombinant interferon gamma (rIFN gamma) and lipopolysaccharide (LPS) was investigated. Ten units per millilitre of rIFN gamma increased surface expression of MHC class I and class II (DR alpha, DP alpha, and DQ alpha) molecules but not other surface antigens examined. The upregulation of MHC class II expression was specifically blocked by rIFN gamma specific monoclonal antibodies and determination of a dose/response curve established that the minimum concentration of rIFN gamma required for increased class II expression was 0.1 U ml-1 and for increased class I expression, 1 U ml-1. Northern blot analysis indicated that rIFN gamma mediated increases in surface MHC class I and class II expression were due to increased levels of specific mRNA. Using Northern blot analysis and homologous human cDNA probes we failed to detect mRNA encoding the cytokines IL-1 alpha, IL-1 beta, and TNF alpha in RNA extracted from freshly isolated macrophages or macrophages cultured in medium alone. Exposure of macrophages to LPS increased production of all three cytokines although kinetics of upregulation varied. TNF alpha mRNA was induced to maximal levels within 1 h, declining thereafter. IL-1 alpha mRNA was detected at 1 h post stimulation with a maximal level at 5 h, but none at 24 h. In contrast, IL-1 beta mRNA was not detected until 5 h after stimulation with a low level remaining at 24 h. Dose response analysis indicated that LPS concentrations of 100 pg ml-1 induced detectable levels of TNF alpha mRNA while levels as low as 10 pg ml-1 induced secretion of bioactive IL-1. Analysis of the kinetics of secretion of bioactive IL-1 from LPS stimulated macrophages indicated that levels peaked at 24 h post stimulation.  相似文献   

8.
The role of prostaglandin F2 alpha (PGF2 alpha) in embryonic loss following induced endotoxemia was studied in mares that were 21 to 44 days pregnant. Thirteen pregnant mares were treated with a nonsteroidal anti-inflammatory drug, flunixin meglumine, to inhibit the synthesis of PGF2 alpha caused by Salmonella typhimurium endotoxin given IV. Flunixin meglumine was administered either before injection of the endotoxin (group 1, -10 min; n = 7), or after endotoxin injection into the mares (group 2, 1 hour, n = 3; group 3, 2 hours, n = 3); 12 pregnant mares (group 4) were given only S typhimurium endotoxin. In group 4, the secretion of PGF2 alpha, as determined by plasma 15-keto-13,14-dihydro-PGF2 alpha concentrations, was biphasic, initially peaking at 30 minutes followed by a second, larger peak approximately 105 minutes after the endotoxin was given IV. When flunixin meglumine was administered at -10 minutes, synthesis of PGF2 alpha was inhibited for several hours, after administration of flunixin meglumine at 1 hour, the second secretory surge of PGF2 alpha was blocked, and administration of the drug at 2 hours did not substantially modify the secretion of PGF2 alpha. Plasma progesterone concentrations were unchanged after endotoxin injections were given in group 1. In group 2, progesterone values decreased less than 2 ng/ml and remained low for several days. In group 3 and group 4, progesterone concentrations decreased to values less than 0.5 ng/ml by 48 hours after endotoxin injections were given.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

9.
By inoculating Klebsiella pneumoniae into the teat canals of mammary glands, coliform mastitis was induced experimentally in 6 lactating cows. Release of eicosanoids, histamine, and serotonin in plasma and milk was studied in response to 2 doses of K pneumoniae. A low dose (mean, 5,000 organisms/ml) was inoculated into cows 1 through 4, and a high dose (mean, 200,000 organisms/ml) was inoculated into cows 5 and 6. Milk and blood samples were collected before inoculation (0 hours), and hourly, from 3 to 24 hours after inoculation. Concentrations of prostaglandin F2 alpha (PGF2 alpha), prostaglandin E (PGE), thromboxane B2 (TxB2), histamine, and serotonin were measured in plasma and milk obtained from control (NaCl solution-inoculated) and infected quarters. Fluorometric analysis of milk from infected quarters revealed significantly increased histamine and serotonin concentrations regardless of the dose of K pneumoniae. The mean (+/- SEM) peak concentrations of histamine were significantly (P less than 0.01) increased from the preinoculation value of 44 (+/- 12) ng/ml to 312 (+/- 104) ng/ml in milk from infected quarters and 72 (+/- 24) ng/ml in milk from control quarters. The mean peak concentration of serotonin increased significantly from the preinoculation concentration of 436 (+/- 37) ng/ml to 1,754 (+/- 662) ng/ml and 4,867 (+/- 1,248) ng/ml in milk from control (P less than 0.02) and infected (P less than 0.001) quarters, respectively. However, serotonin concentration in milk from infected quarters was approximately 2.8 times greater than that in milk from control quarters. Concentrations of PGF2 alpha, PGE, and TxB2 in milk and plasma were evaluated by radioimmunoassay.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

10.
Blood monocytes and alveolar macrophages (AM) were harvested from foals (aged 46 days to 6 months) and cultured in either medium alone or medium containing 10 micrograms/ml bacterial lipopolysaccharide (LPS). After 24 h, culture supernates were collected and analyzed for cytotoxic activity on sensitized L929 cells. Both monocytes and AM that had been treated with LPS produced significantly more cytotoxic activity than the same cell type exposed to medium lacking LPS. LPS-treated macrophages secreted significantly more cytotoxic activity (120 +/- 17.8 U/ml) than did LPS-treated monocytes (47.3 +/- 17.0 U/ml); however, constitutive production of cytotoxin by monocytes was higher (16.7 +/- 4.1 versus 1.2 +/- 1.2 U/ml). The identification of the cytotoxin as tumor necrosis factor (TNF) was strongly suggested by its reactivity with a rabbit antiserum directed against the N-terminal 15 amino acids of human TNF. TNF secretion by AM increased in a dose-dependent manner between LPS concentrations of 0.0001 and 1 microgram/ml, then leveled off. Most of the cytotoxic TNF activity produced by AM was secreted within the first 8 h after initial contact with LPS. Macrophage supernatant TNF was stable over a pH range of 6-11, but lost activity when kept at a pH less than 6. Equine TNF also was destroyed by exposure for 1 h to temperatures more than 60 degrees C. TNF bioactivity was recovered as a single peak after crude macrophage supernate was subjected to analysis by either anion exchange or gel filtration chromatography (molecular weight approximately 56,000).  相似文献   

11.
Glucocorticoids inhibit the plasma vasopressin responses to hemorrhage and hypoxia in dogs. Attempts to demonstrate glucocorticoid inhibition of vasopressin secretion in fetal sheep have been unsuccessful, suggesting the possibility that there is an influence of development on the expression of this interaction, or that the interaction cannot be demonstrated in all mammalian species. This study was designed to investigate these two possibilities. Adult ewes chronically prepared with carotid arterial loops, were subjected to 5 hr infusions of cortisol at a rate of 6 ug/kg min or vehicle (5% ethanol in saline). The infusion of cortisol increased plasma cortisol concentration from 26 +/- 3 to 46 +/- 8 ng/ml, while vehicle infusion was associated with a decrease in plasma cortisol concentration from 23 +/- 4 to 15 +/- 3 ng/ml. One hr after the end of the cortisol or vehicle infusions, vasopressin secretion was stimulated by arterial hypotension produced by 10 min infusions of sodium nitroprusside (20 ug/kg min). Nitroprusside decreased arterial blood pressure equally in both groups. Plasma vasopressin concentrations were increased to peak concentrations of 92 +/- 33 and 116 +/- 20 pg/ml in the vehicle- and cortisol-infused groups, responses which were not significantly different as tested by ANOVA. We conclude that increases in plasma cortisol concentration, equal to those observed during responses to stressors, do not inhibit vasopressin secretion in this species.  相似文献   

12.
Secretion of tumor necrosis factor (TNF) by equine mammary exudate macrophages (MEM phi) exposed to bacterial lipopolysaccharide (LPS) was dose-dependent and was maximal (216.5 +/- 51.9 U/ml) at 100 micrograms LPS/ml, the highest concentration tested. All concentrations of dexamethasone tested (10(-8) to 10(-4) M) significantly (P less than or equal to 0.05) inhibited TNF production by MEM phi when the agent was added 1 hour before LPS. Pretreatment with pentoxifylline at concentrations greater than 3 micrograms/ml also significantly (P less than or equal to 0.05) reduced secretion of TNF by MEM phi. The inhibitory effect of dexamethasone (10(-4) M) was observed when the agent was added to MEM phi from 30 minutes before until 4 hours after LPS. Pentoxifylline (100 micrograms/ml) significantly (P less than or equal to 0.05) suppressed TNF when added from 2 hours before until 2 hours after LPS; however, when pentoxifylline addition was delayed until 8 hours post-LPS, TNF production was enhanced. These apparent inhibitory effects of dexamethasone and pentoxifylline were not due to reduced macrophage viability or to interfering effects of the agents at the level of the TNF bioassay.  相似文献   

13.
To determine the effect of the hyperadrenal state on corpus luteum (CL) function, we treated intact and adrenalectomized (ADRX) heifers with adrenocorticotropin (ACTH) and hydrocortisone. ACTH treatment of intact heifers by infusion of 1 mg alpha 1-24 ACTH/24 hr from day 2 to 25 of an estrous cycle increased progesterone concentrations in plasma to 4 +/- .52 ng/ml plasma on days 3 to 4. Thereafter, progesterone concentrations declined, indicating severe suppression of CL function as compared to that of control heifers. Similar infusions of ACTH to ADRX heifers did not alter CL function as reflected by progesterone concentrations in jugular plasma. Infusion of ADRX animals with hydrocortisone succinate (100 mg/24 hr) decreased progesterone in plasma during the cycle, with maximum values averaging less than 4 ng/ml, compared to concentrations of 6 to 7 ng/ml in control ADRX heifers. Chronic administration of ACTH or hydrocortisone to heifers caused a decreased progesterone secretion during the luteal phase of the estrous cycle. On the basis of these results, we suggest that stress, as indicated by the hyperadrenal state, could inhibit progesterone secretion by the corpus luteum.  相似文献   

14.
Plasma concentrations of porcine growth hormone (PGH) were similar in healthy pigs and those with atrophic rhinitis (AR), therefore, observed reduced growth rates and feed efficiency in naturally infected pigs with AR were not attributed to low concentrations of plasma PGH. Also, pituitary glands in both groups of pigs were responsive to growth hormone-releasing hormone (GHRH) challenge by increasing PGH secretion. Administration of clonidine hydrochloride to pigs naturally infected with AR failed to elicit any significant change (5.3 +/- 1.4 ng/ml) in the plasma concentration of PGH within a 45-minute bleeding interval. The pretreatment concentrations of PGH were similar in specific-pathogen-free toxin-treated and specific-pathogen-free control groups, but they increased significantly in toxin-treated pigs (20.7 +/- 8.2 ng/ml) within 15 minutes after GHRH injection. Porcine growth hormone release in toxin-treated pigs was variable; however, all pigs did not respond to GHRH administration: 3 responded with an increase in PGH release (35.6 +/- 10.6 ng/ml), 2 did not respond (6.7 +/- 0.5 ng/ml), and 1 had a decrease in PGH release (3.9 ng/ml). Therefore, the observed reduced growth rates reported in the literature may be attributed to factors at the target level of PGH action, such as insufficient or down-regulation of PGH receptors, changes or impaired ability in the PGH receptor-binding characteristics, and inability of PGH receptor complex to transduce signal. Toxins are known to modulate signal transduction pathways. It has been speculated that serotype-D Pasteurella multocida toxin may influence growth by its effect on signal transduction from PGH receptor complex on the cell membrane to the interior of the cell.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

15.
探讨橙皮苷对3种霉菌毒素处理的HepG2细胞增殖和迁移作用的影响。采用MTT、Griess、细胞划痕愈合试验分别检测细胞活力、细胞分泌NO、细胞迁移率。结果3种毒素对HepG2细胞增殖的影响随毒素浓度的增加呈现先促进后抑制的作用,低浓度DON、OTA(0.04μmol/L和0.08μmol/L),ZEN(<2μmol/L)显著提高HepG2细胞活力及促进增殖,高浓度霉菌毒素明显降低HepG2细胞活力及抑制细胞增殖。与霉菌毒素组比较,橙皮苷组HepG2细胞活力降低及增殖减弱,表示橙皮苷能缓解霉菌毒素对细胞的毒性。与空白对照组比较,霉菌毒素组HepG2分泌NO量显著降低,不同浓度及不同霉菌毒素对NO分泌没有明显影响;与霉菌毒素组比较,橙皮苷组不同浓度DON处理的细胞分泌NO差异不显著。低浓度DON毒素(0.08μmol/L^2μmol/L)处理HepG2细胞24、36、48 h后,DON毒素能极显著促进HepG2细胞迁移,随着霉菌毒素对细胞处理时间延长细胞迁移快,而高浓度DON毒素(10μmol/L、50μmol/L)对促细胞迁移影响显著低于低浓度DON。结果低浓度DON霉菌毒素促进HepG2细胞增殖及迁移,表明DON毒素对HepG2具有潜在的致癌性,橙皮苷能抑制HepG2细胞增殖及缓解霉菌毒素毒性的作用。  相似文献   

16.
OBJECTIVES: To evaluate the effects of equine recombinant interleukin-1alpha (rEqIL-1alpha) and recombinant interleukin-1beta (rEqIL-1beta) on proteoglycan metabolism and prostaglandin E2 (PGE2) synthesis by equine articular chondrocytes in explant culture. SAMPLE POPULATION: Near full-thickness articular cartilage explants (approx 50 mg) harvested from stifle joints of a 3-year-old and a 5-year-old horse. PROCEDURE: Expression constructs containing cDNA sequences encoding EqIL-1alpha and EqIL-1beta were generated, prokaryotically expressed, and the recombinant protein purified. Near full-thickness articular cartilage explants (approx 50 mg) harvested from stifle joints of a 3-year-old and a 5-year-old horse were separately randomized to receive rEqIL-1alpha or rEqIL-1beta treatments 10 to 500 ng/ml). Proteoglycan release was evaluated by 1,9-dimethylmethylene blue spectrophotometric analysis of explant media glycosaminoglycan (GAG) concentration and release of 35S-sulfate-labeled GAG to explant media. Proteoglycan synthesis was assessed by quantification of 35S-sulfate incorporation into proteoglycan. Explant media PGE2 concentrations were evaluated using a PGE2-specific enzyme-linked immunoassay. Data were collected at 48-hour intervals and normalized by DNA content. RESULTS: Proteoglycan release was induced by rEqIL-1alpha and rEqIL-1beta at concentrations > or =0.1 ng/ml, with 38 to 76% and 88 to 98% of total GAG released by 4 and 6 days, respectively. Inhibition of proteoglycan synthesis (42 to 64%) was observed at IL-1 concentrations > or = 0.1 ng/ml at 2 and 4 days. Increased PGE2 concentrations were observed at IL-1 concentrations > or = 0.1 ng/ml at 2 and 4 days. CONCLUSIONS AND CLINICAL RELEVANCE: The rEqIL-1 induced potent concentration-dependent derangement of equine chondrocyte metabolism in vitro. These findings suggest this model may be suitable for the in vitro study of the pathogenesis and treatment of joint disease in horses.  相似文献   

17.
Plasma concentrations of prolactin and corticosterone were determined in hourly samples collected over a 25-hr period from unrestrained turkey hens exhibiting incubation (broody) behavior. Hens were maintained in cages on a 14 hr light: 10 hr dark photoperiod. Mean plasma prolactin concentration increased significantly late in the dark period to reach maximum daily levels of 496 ng/ml at the start of the photophase. However, a well-defined daily rhythm in prolactin secretion was not evident. Plasma corticosterone concentration showed a significant daily rhythm characterized by a major secretory peak (7.14 ng/ml) in the middle of the light period and a smaller, less well-defined peak (4.11 ng/ml) during the dark period. Both prolactin and corticosterone secretion ranged widely throughout the day in individual hens in a manner suggestive of pulsatile hormone secretion. This study demonstrates that the extremely high prolactin concentrations characteristic of the incubating turkey hen reflect large, dynamic changes in plasma prolactin concentrations occurring throughout the photoperiod, rather than a constantly high level of prolactin secretion.  相似文献   

18.
ABSTRACT: The mycotoxin T-2 toxin and Salmonella Typhimurium infections pose a significant threat to human and animal health. Interactions between both agents may result in a different outcome of the infection. Therefore, the aim of the presented study was to investigate the effects of low and relevant concentrations of T-2 toxin on the course of a Salmonella Typhimurium infection in pigs. We showed that the presence of 15 and 83 μg T-2 toxin per kg feed significantly decreased the amount of Salmonella Typhimurium bacteria present in the cecum contents, and a tendency to a reduced colonization of the jejunum, ileum, cecum, colon and colon contents was noticed. In vitro, proteomic analysis of porcine enterocytes revealed that a very low concentration of T-2 toxin (5 ng/mL) affects the protein expression of mitochondrial, endoplasmatic reticulum and cytoskeleton associated proteins, proteins involved in protein synthesis and folding, RNA synthesis, mitogen-activated protein kinase signaling and regulatory processes. Similarly low concentrations (1-100 ng/mL) promoted the susceptibility of porcine macrophages and intestinal epithelial cells to Salmonella Typhimurium invasion, in a SPI-1 independent manner. Furthermore, T-2 toxin (1-5 ng/mL) promoted the translocation of Salmonella Typhimurium over an intestinal porcine epithelial cell monolayer. Although these findings may seem in favour of Salmonella Typhimurium, microarray analysis showed that T-2 toxin (5 ng/mL) causes an intoxication of Salmonella Typhimurium, represented by a reduced motility and a downregulation of metabolic and Salmonella Pathogenicity Island 1 genes. This study demonstrates marked interactions of T-2 toxin with Salmonella Typhimurium pathogenesis, resulting in bacterial intoxication.  相似文献   

19.
Thirteen female Bedouin goats living in arid land of Algeria Sahara desert were used in this study. These goats were pregnant but they sustained an abortion because of unidentified causes. None of the goats showed any signs of general disease. Plasma concentrations of caprine pregnancy‐associated glycoproteins (cPAGs) and progesterone (P4) were determined during pregnancy using radioimmunoassay. The cPAGs concentration was undetectable (<0.8 ng/ml) throughout the first 2 weeks of gestation. From week 3 after mating, cPAGs concentration was detectable with significant individual variations (p < 0.05) reaching a maximum secretion (436.1 ng/ml). Throughout gestation, cPAGs concentration remained relatively constant but decreased few days before abortion, on an average of 9.2 ± 1.2 days (n = 11), except for two females where the concentrations decreased later (1–2 days before abortion). One or two peaks of cPAGs concentrations (in 4/13 and in 9/13 females, respectively) have been measured few weeks before abortion (77–124 days after mating), when a decline of cPAGs was detected. The P4 concentration increased after mating, and was high from the first week till the end of pregnancy. The P4 concentration (9.1 ± 0.9 ng/ml) decreased rapidly (<0.5 ng/ml) after 4 ± 0.7 days (n = 6) or 9.4 ± 1.6 days (n = 7) before abortion. A positive relationship (p < 0.01) was found between P4 and cPAGs concentrations during gestation. Results indicate that cPAGs and P4 measurements can be used for monitoring gestation and for abortion prediction.  相似文献   

20.
The objective of this study was to evaluate luteinizing hormone (LH) and luteal progesterone (P4) secretion in systemic blood and blood near the ovaries in Mangalica (M) and Landrace (L) gilts by implanting catheters into the Vena jugularis and the Vena cava caudalis via the Vena saphena, respectively. Furthermore, leptin was analyzed in jugular vein blood. Blood was collected twice daily from day 7 to day 19 of the oestrous cycle and frequently (10-min intervals for 6 h) on day 9, day 12 and day 15 in M (n=3) and L gilts (n=4). L gilts had congruent pulsatile LH secretion in both veins, but the LH concentrations in M were always below the assay sensitivity during the luteal phase. In both breeds, episodic P4 secretion was found in the jugular and caval veins, and both sampling site and breed had an influence on P4 secretion (P<0.05). The mean concentration of P4 was higher (P<0.01) in utero-ovarian blood (75.8+/-5.3 in M; 49.6+/-4.2 ng/ml in L) than in the periphery (31.3+/-2.0 in M; 21.2+/-1.8 ng/ml in L). M pigs had a lower number of corpora lutea (9.7+/-2.3 vs. 20.5+/-4.4), and analysis of the P4 secretion ratio per corpus luteum revealed an influence of breed (P<0.01). This ratio was significantly higher in M (3.8+/-0.3 and 8.7+/-0.7 ng/ml) compared with the L gilts (1.4+/-0.1 and 2.8+/-0.3 ng/ml) in the jugular and caval veins, respectively. Blood sampling from the Vena cava caudalis is potentially more precise than from the Vena jugularis for evaluation of ovarian P4 secretion. Both the higher P4 concentration and increased leptin secretion (11.3+/-0.6 vs. 3.0+/-0.1 ng/ml, P<0.05) and consequently the altered LH secretion pattern in the Mangalica may contribute to the lower fecundity of this breed.  相似文献   

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