Peripheral Progesterone Levels Research Articles

Progesterone receptor distribution in the human hypothalamus and its association with suicide

The human hypothalamus modulates mental health by balancing interactions between hormonal fluctuations and stress responses. Stress-induced progesterone release activates progesterone receptors (PR) in the human brain and triggers alterations in neuropeptides/neurotransmitters. As recent epidemiological studies have associated peripheral progesterone levels with suicide risks in humans, we mapped PR distribution in the human hypothalamus in relation to age and sex and characterized its (co-) expression in specific cell types. The infundibular nucleus (INF) appeared to be the primary hypothalamic structure via which progesterone modulates stress-related neural circuitry. An elevation of the number of pro-opiomelanocortin+ (POMC, an endogenous opioid precursor) neurons in the INF, which was due to a high proportion of POMC+ neurons that co-expressed PR, was related to suicide in patients with mood disorders (MD). MD donors who died of legal euthanasia were for the first time enrolled in a postmortem study to investigate the molecular signatures related to fatal suicidal ideations. They had a higher proportion of PR co-expressing POMC+ neurons than MD patients who died naturally. This indicates that the onset of endogenous opioid activation in MD with suicide tendency may be progesterone-associated. Our findings may have implications for users of progesterone-enriched contraceptives who also have MD and suicidal tendencies.

Risk Factors for Monozygotic Twins in IVF-ICSI Cycles: a Case-Control Study.

In vitro fertilization (IVF) is associated with a higher incidence of monozygotic twin pregnancies, which are known to be burdened by a higher risk of main obstetric complications. The reasons behind this association are still unclear. In the present study, we therefore investigate the risk factors for monozygotic twinning in pregnancies achieved by IVF. We conducted a multicenter retrospective case-control study. All IVF cycles performed between 2014 and 2019 at the infertility units of two Italian academic institutes were retrospectively reviewed. Only pregnancies obtained with single embryo transfer were eligible. A total of 50 monozygotic twin pregnancies (cases) were identified and matched in a 1:5 ratio to 250 singleton pregnancies (controls) by study center and study period. Monozygotic twin pregnancies were diagnosed by ultrasound. Women experiencing miscarriage could be included provided that the pregnancy loss occurred after a definitive diagnosis of monozygotic twin pregnancy. Demographic, clinical, and embryological characteristics were retrieved from patients' charts. Overall, the incidence of monozygotic twin pregnancies was 1.2% (50 out of 4016 single embryo transfers). At univariate analyses, statistically significant differences emerged for BMI, peripheral levels of estradiol and progesterone at the time of hCG administration, total number of retrieved suitable oocytes, freezing-thawing cycles, and assisted hatching. After performing a multivariate logistic analysis, only assisted hatching remained significantly associated with monozygotic twinning (adjusted odds ratio 2.32, 95%CI 1.03-5.25). Blastomere separation during the passage through this artificial hole or interference with the signaling pathway within the embryo could be the mechanisms involved.

Allopregnanolone and progesterone in estradiol treated severe postpartum depression and psychosis – Preliminary findings

BackgroundPostpartum affective disorders may be associated with dysregulation of gonadal steroids. We investigated peripheral levels of allopregnanolone and progesterone in a combined group of women with postpartum onset of severe depression and/or psychosis who, as previously reported, responded with rapid symptom remission during sublingual estradiol treatment. The aim was to assess differences in allopregnanolone and progesterone between patients and healthy controls at baseline, and hormonal changes during estradiol treatment and symptom remission in patients. MethodsAllopregnanolone and progesterone in serum were analyzed with radioimmunoassay before and four weeks after initiation of sublingual estradiol treatment in ten women with postpartum depression and four women with postpartum psychosis (ICD-10). Twenty-eight healthy postpartum controls were included for baseline comparison. ResultsAllopregnanolone declined significantly during estradiol treatment while there was a trend for lower baseline allopregnanolone levels in patients compared with healthy postpartum controls. The ratio between allopregnanolone and progesterone was significantly lower in patients compared with controls and it remained unchanged after clinical recovery. LimitationsThis study is a secondary analysis of two estradiol treatment studies based on availability of samples for the analysis of allopregnanolone. Healthy controls were assessed earlier after delivery. Data on potential confounders (somatic health, breastfeeding, other medication) were not available. ConclusionsThese preliminary findings suggest that clinical recovery of severe postpartum depression and psychosis during estradiol treatment does not seem to depend on increasing levels of allopregnanolone. Differences in progesterone metabolism may constitute a risk factor for severe postnatal affective dysregulation.

Pregnancy rate after fixed-time artificial insemination of suckled beef cows subjected to a cosynch protocol with either buserelin or hCG as ovulation inducing agent

Abstract The aim of this study was to document the effectiveness of the implementation of a cosynch protocol and fixed time artificial insemination in suckled beef cows kept under range conditions in Germany. In addition, the suitability of hCG administration as an alternative to the GnRH analog buserelin (Receptal®, Intervet, Germany) as ovulation inducing agent was investigated. The 120 Simmental and 120 German Angus cows were randomly divided into four groups. Cows of Group 1 were subjected to the classical cosynch protocol, constituting administration of GnRH, followed, 7 days later, by prostaglandin F2α and, after 2 days, another GnRH administration and simultaneous AI. In cows of Group 2, hCG was administered instead of GnRH at the beginning of the protocol, in Group 3 at the end and in Group 4 at the beginning and at the end. Inseminations with frozen-thawed semen from Limousin, Charolais, Simmental and German Angus sires were carried out by the same skilled inseminator. Blood samples collected 11 days before and on days 0, 7 and 9 of the cosynch protocol were analyzed for progesterone concentration. The study extended over three consecutive years. Of the total of 489 inseminations, 53% resulted in pregnancies (Simmental: 60%; German Angus: 48%). When GnRH was administered at the beginning and at the end of the cosynch protocol (Group 1), pregnancy rate across breeds was 65% (Simmental: 61%; German Angus: 68%); likewise when hCG was substituted for GnRH at the end of the protocol (Group 2). Pregnancy rate across breeds reached 48% when hCG was given at the beginning (Group 3) and was lowest (37%) when hCG was given at the beginning and at the end. German Angus cows responded particularly poorly to hCG treatment. In cows that were cycling, as indicated by serum progesterone levels 11 and 0 days before treatment, pregnancy rate across breeds and treatments was highest (57%) if the cosynch protocol was initiated at a stage of the cycle when peripheral progesterone levels were on the rise. In non-cycling cows, representing only 13% of the herd, contrary to expectation pregnancy rate reached 65%. In conclusion, implementation of fixed-time artificial insemination in suckled beef cows kept under local range conditions led to satisfactory pregnancy results, especially if the cosynch protocol was initiated at a stage when progesterone levels were on the rise. Substitution of hCG for GnRH proved to be of no advantage; in fact, when administered at the beginning of the protocol it resulted in a detrimental effect on fertility.

Peripheral Progesterone Level and Times to Estrus and Ovulation in Female Dromedary Camels Treated with CIDR-eCG-hCG Programs

This study was conducted to characterize serum progesterone (P4) profiles during CIDReCG- hCG superovulatory program and to investigate the effect of time of eCG administration on the superovulatory response in dromedary camels. Controlled internal drug release (CIDR) was inserted intravaginally for 14 days in eleven dromedary females. Two days before CIDR withdrawal, group 1 (n=6) received 3000 iu eCG im, group 2 (n=5) received the same dose at CIDR withdrawal. All received 1500 iu hCG two days after CIDR withdrawal (d+2). Animals were observed for estrus and mated with a fertile male. Serum was obtained for progesterone. The ovaries were examined using ultrasound. An increase in serum P4 was observed within 20min of CIDR insertion with peak level attained by 4h (P<0.0001). There were no differences in P4 between group 1 and 2. Estrus and ovulation occurred nonsignificantly earlier in group 1 (4.8±0.9d and 8.2±1d) than in group 2 (6±0.7d and 9±1d), respectively. Number of corpora lutea by d+14 did not differ between group 1 (4.6±0.7) and group 2 (5.2±1.5). In conclusion, early administration of eCG did not hasten estrus or ovulation or the function of the CLs in super-stimulated female dromedaries compared with its administration at the time of CIDR withdrawal. These data may help in designing fixed time superovulation programs in dromedary camels.

PP.23.02

Objective: Since aldosterone and cortisol levels vary during the menstrual cycle, and are utilised in the interpretation of adrenal venous sampling (AVS) to differentiate unilateral from bilateral primary aldosteronism, outcome of AVS in premenopausal women could possibly be influenced by when the collections are made. We assessed the effect of phase of the menstrual cycle on both adrenal and peripheral venous aldosterone and cortisol levels and on serum female sex steroid levels during AVS. Design and method: In 23 premenopausal women with primary aldosteronism undergoing AVS, levels of aldosterone, cortisol, progesterone, estradiol, LH and FSH levels were compared, depending on whether collected during the follicular or luteal phase Results: Based on results at AVS, 10 women had unilateral over-production of aldosterone, and 13 bilateral. Unilateral aldosterone over-production was observed more frequently in women undergoing AVS during the luteal phase compared with the follicular phase (7/10 = 70% vs 3/13 = 23%; p < 0.05). Simultaneously collected peripheral levels of progesterone (p < 0.0001), estradiol (p < 0.05) and aldosterone (p < 0.05) and bilateral adrenal venous levels of aldosterone (p < 0.01) and cortisol (p < 0.01) were higher in those sampled during the luteal phase. Importantly, higher/lower side adrenal venous aldosterone/cortisol ratios (i.e. lateralization indices) were higher during the luteal phase than follicular [median 11 (range 2.94–96) vs 2 (1.23–35), (p < 0.05)]. Conclusions: The phase of the menstrual cycle during which samples are collected significantly affects the levels of aldosterone and cortisol used to interpret AVS. A risk of false lateralization appears to be present when AVS is performed during the luteal phase, but this requires confirmation with larger patient numbers, ideally with studies in each patient during both phases. Meanwhile, recording of the phase of the cycle during which AVS is performed should be encouraged.

Placental malaria and modulation of immune and hormonal responses in Cameroonian women

Adverse pregnancy outcomes place the lives of mother and new born babies in jeopardy, especially in Sub Saharan Africa. Although a well-balanced network of the pregnancy-associated hormones and lipid fractions is necessary for healthy pregnancy, the profiles of some of these biomarkers alongside those of some cytokines in relation to placental malaria (PM) and poor pregnancy outcomes are unknown. Therefore between 2013 and 2014, paired peripheral and placental blood samples were collected from 135 Cameroonian women at delivery. Parasitaemia was determined microscopically and haemoglobin levels using Coulter counter. Plasma levels of cytokines (IFN-γ, IL-1β and IL-7) and pregnancy-associated hormones (17β oestradiol and progesterone) were measured by ELISA and the levels of lipid fractions: total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C) and triglycerides (TG) determined by Colorimetric enzymatic methods. Parasitaemia was inversely related to parity, haemoglobin levels and birth weight (P≤0.019). While the levels of IFN-γ and cholesterol (total, HDL and LDL) were higher in peripheral plasma, those of IL-1β, 17β oestradiol, progesterone and triglyceride were higher in placental blood (P<0.001). Absence of PM was significantly associated with high plasma levels of IFN-γ, IL-7 and HDL-C and low plasma levels of 17β oestradiol and TG. Moreover, IL-7 levels correlated positively and significantly with haemoglobin levels and with both peripheral and placental levels of progesterone. Baby birth weight increased with plasma levels of progesterone and HDL-C. Levels of IFN-γ correlated positively and significantly with HDL-C, but negatively with LDL-C; thus, might prevent pregnant women from atherogenic risk. Study of the inter-relationship between hormones, cytokines and lipids revealed that the association between IL-7 and progesterone and/or some lipid fractions followed inverse trends from that of IFN-γ.These results suggest that in PM, IFN-γ and IL-7 might protect against poor pregnancy outcomes, which decrease plasma levels of progesterone, maternal haemoglobin and HDL-C, leading to low birth weight. However, these cytokines may act differently with regards to progesterone and some lipid fractions. PM may also lower plasma levels of HDL-C and increase that of TG which is the most important risk factor for cardiovascular disorders and consequently poor pregnancy outcomes.

A field study to unravel factors that are significantly associated with the secretory activity of the corpus luteum during the first three postpartum cycles in high yielding dairy cows, based on the amount of steroidogenic and endothelial cells present in the luteal tissue.

Fourteen multi- and eight primiparous high-yielding dairy cows were followed from the first till the fourth ovulation postpartum. Cows were randomly divided into two groups and supplemented with soybean (group I; n = 11) or rapeseed meal (group II; n = 11). Both groups were subjected to a biopsy sampling of the corpus luteum (CL) at cycle day 9. The luteal capillary network (visualized by Bandeiraea simplicifolia) was denser in cycles 2 and 3 (p = 0.0005). The same was seen for the surface occupied by steroidogenic cells (visualized by 3β-hydroxysteroiddehydrogenase) (p = 0.0001). The peripheral blood progesterone concentration showed an increasing trend with increasing cycle number and was higher in primiparous cows (p = 0.013), which had also larger glands on cycle day 9. The area occupied by endothelial cells was positively correlated with the area occupied by steroidogenic cells (r = 0.59; p < 0.0001). Both the areas occupied by endothelial and by steroidogenic cells were negatively correlated with the blood concentration of nonesterified fatty acids (NEFAs) (respectively, r = -0.377; p = 0.004 and r = -0.355; p = 0.007). We can conclude that primiparous cows generally have higher peripheral progesterone levels during the first three cycles after calving which is associated with a larger CL. In comparison with those of the first post-partum cycle, corpora lutea of cycles 2 and 3 have a denser capillary network and a larger area of steroidogenic cells, while these are only associated with a trend of higher peripheral progesterone concentrations.

71 EFFECTS OF A CONTROLLED DIETARY EXPOSITION TO ZERALENONE ON SELECTED REPRODUCTIVE PARAMETERS IN DAIRY COWS

Whole plant corn silage is an important component of dairy cow nutrition. Growing conditions in a moderate climate, as are present in large parts of Europe and North America, are often beneficial for mould contaminations to occur. Very commonly, varieties of Fusarium spp. grow on the corn plant producing the non-steroidal estrogenic mycotoxin zearalenone (ZEN). Numerous studies have shown that ZEN massively interacts with the porcine reproductive system. Nevertheless, only a few studies have assessed the possible effects on dairy cows, most publications being field studies following accidental exposure. Therefore, it was aim of the present study to assess the effects of a controlled dietary exposition on selected reproductive parameters in dairy cows. The chosen exposure concentration was within the range of the ‘Commision Recommendation on the presence of deoxynivalenol, zearalenone, ochratoxin A, T-2 and HT-2 and fumonisins in products intended for animal feeding’ of the European Union. Corn plants were artificially inoculated with Fusarium spp. and the silage obtained from the whole plant was analysed to determine to which degree the silage contained ZEN. Thirty Holstein Friesian cows and heifers (aged between 2 years 3 months and 5 years at calving) were allocated to 3 groups with 10 animals each: control (CTL), uncontaminated silage; ZEN 50, silage with 0.25 mg of ZEN/day; and ZEN 100, silage with 0.5 mg of ZEN/day. The contaminated rations were distributed by automated feeding stations to ensure an equal uptake. Feeding began 7 days post-parturition. Blood samples were obtained twice weekly for 12 weeks and were analyzed regarding the progesterone level via radioimmunoassay. At the same time, the oestrous cycle was monitored by ultrasonography. Furthermore, the size of the corpus luteum (CL) was measured 7 ± 2 days after the third ovulation. Simultaneously, the luteal blood flow was documented via Doppler ultrasonography. The peripheral blood progesterone level (xgeom. ± CV; CTL: 9.3 ± 1.7; ZEN 50: 8.5 ± 1.6; ZEN100: 7.1 ± 1.5) did not differ among groups. Furthermore, it was not possible to detect differences in luteal blood flow, size of the CL (mean ± SD; CTL: 6.4 ± 1.7 cm2; ZEN50: 5.9 ± 1.3 cm2; ZEN 100: 5.0 ± 1.0 cm2) or the ratio of luteal size and size of the area supplied with blood (CTL: 0.1 ± 0.1; ZEN 50: 0.1 ± 0.0; ZEN 100: 0.1 ± 0.1). Although the mean length of the oestrous cycles (n = 60; distributed among groups) did not differ among groups (CTL: 24.0 ± 1.7 days; ZEN 50: 27.2 ± 1.6 days; ZEN 100: 27.7 ± 1.4 days), it was possible to detect an interaction between the age of the animal and the treatment regarding the cycle length in tendency (P &lt; 0.07) by two-way ANOVA. The results of the present study indicate that, independent of the age of the animal, exposure to ZEN even within recommended dosages might result in an endocrine disruption in dairy cows. A larger sample size would contribute to the verification of these findings. Further analyses regarding the peripheral level of 17β-estradiol as well as molecular examinations are under progress.

The effect of hCG, administered in diestrus, on luteal, ovarian and uterine blood flow, peripheral progesterone levels and pregnancy rates in mares

Although advances in the management of brood mares have led to an increase in conception rates, early embryonic loss is still a major concern in equine practice. However, administration of hCG in diestrousmares has been reported to increase pregnancy rates and progesterone production. The aim of this study was to analyze the effects of a postovulatory hCG-treatment on luteal, ovarian and uterine blood flow, peripheral serum progesterone concentrations and pregnancy rates in the mare. Thirty-four mares were inseminated, 17 with cooled and 17 mares with frozen semen, and randomly assigned to three experimental groups after ovulation (D0). Group 1 (n 1⁄4 12) served as untreated control, Group 2 (n1⁄411) received a single intravenous injection of 2500 IU hCG on D5, and Group 3 (n 1⁄4 11) got an analogous hCG-application on D 11 of the cycle. On D0 during the first 12 h post ovulation colour Doppler ultrasonography was performed every 4 h, and afterwards in 12-h-intervals until D3 in all groups. The control group was examined once daily until D13. Mares in the treatment groups were examined once daily until the hCG-administration. Thereafter ultrasonographic examinations were performed every four hours for the first 12 h and in 12-h-intervals for the following three days. The total as well as the perfused luteal area, and the blood flow

Presence of a Temperature Gradient Among Genital Tract Portions and the Thermal Changes Within These Portions Over the Estrous Cycle in Beef Cows

The aim of the present study was to describe the temperature of the different portions of the female genital tract and their relation to rectal temperature and to investigate the effect of steroid hormones profiles on these variables over the estrous cycle in cattle. Four nonpregnant Japanese Black cows were investigated daily over two successive estrous cycles using a digital thermometer with a long probe and rounded-end sensor to record the temperature of the rectum (RT), vagina (VT), cervix (CT), uterine body (UBT) and uterine horns (UHT). Blood samples were collected immediately before temperature recording to assay peripheral levels of progesterone (P4) and estradiol-17β (E2). Moreover, transrectal ultrasonography was carried out after temperature recording to monitor the ovulatory follicle and track ovulation. During the experiment, the ambient temperature and relative humidity were recorded for further calculation of the temperature humidity index (THI). The temperature within the genital tracts in these cows progressively increased towards the uterine horns from the vagina. The VT, CT, UBT and UHTs were significantly higher in association with peripheral P4 concentrations greater than 4 ng/ml (mid-luteal phase) when compared with lower peripheral P4 concentrations. The VT was more significantly (P<0.01) correlated to the CT, UBT and UHTs than RT. In conclusion, a temperature gradient was present among the vagina, cervix and uterus over the estrous cycle, and changes in peripheral P4 concentrations were associated with the thermal variations within these portions. The VT could be more beneficial than RT in monitoring temperature of deeper portions of the female genital tract in bovine.

57 RELATIONSHIP BETWEEN FETAL ABNORMALITIES AND PERIPHERAL STEROID CONCENTRATIONS DURING GESTATION IN COWS TRANSFERRED WITH EMBRYOS PRODUCED BY SOMATIC CELL NUCLEAR TRANSFER

Cloning of mammals by nuclear transfer frequently results in gestational or neonatal failure with a variety of abnormalities that are likely caused by inappropriate epigenetic reprogramming. Early diagnosis of fetal abnormality is important for efficient production of cloned animals. Sex steroids are produced in the bovine placenta and their levels in the blood might be useful as a measure of fetal well-being, as in humans. The objective of this study was to investigate whether changes in peripheral levels of progesterone and estrogens reflect fetal abnormalities. Donor cells for nuclear transfer were obtained from subculture of cumulus cells retrieved from ovarian follicles of a Japanese Black cow. Recipient oocytes were derived from ovaries obtained at an abattoir and matured in vitro. Metaphase II oocytes were enucleated and each fused with a donor cell by DC pulses. Nuclear transferred oocytes were activated and cultured for 7 days. Embryos developed to the blastocyst stage were transferred into the uterine horn ipsilateral to the ovary bearing the CL of 32 multiparous Japanese Black and Holstein crossbred cows at 7 to 8 days after the day of standing estrus (Day 0). Blood was collected from Day 40 until parturition. Progesterone and estrogens in the blood plasma of 6 recipient cows with full-term delivery were measured by RIA. These profiles were compared with each other and with the changes in a cow made pregnant by MOET. Statistical differences were analyzed with repeated measures ANOVA. Parturition was induced on Day 290. Stillborn, dead, or euthanized calves were subjected to necropsy and histopathological analysis. Pregnant cows were 14, 13, and 9 on Days 30, 60, and 90, respectively. Thereafter, 3 aborted around Days 110, 120, and 190. Six cows delivered calves weighing 45.8 ± 2.1 kg (mean ± SEM) on Days 291 to 293. Their birth weights were greater than those of female calves (31.2 ± 0.4 kg, n = 6) produced by MOET in the same breed. Three calves grew normally until weaning. One was stillborn due to dystocia, but no abnormalities were observed except for large offspring syndrome. One was euthanized 2 days after natural delivery due to ananastasia. Thymic and thyroid hypoplasia, left ventricular dysplasia, and pulmonary fibrosis were found by necropsy. Another calf delivered by Caesarean section died of infirmity 2 days later and had thymic and thyroid hypoplasia. Changes in plasma steroid concentrations were consistent with each other and with those in a MOET cow except the last one, in which progesterone levels tended to be higher during the first trimester and estrogens were lower during the last half of gestation. Progesterone levels tended to be lower in cows bearing a healthy calf than in cows bearing a weak calf before parturition. These results imply that peripheral steroid levels may reflect fetal normality, although large offspring syndrome does not affect their concentrations.

Pregnancy rates and peripheral progesterone levels following Ovsynch or CIDR ovulation synchronization/timed artificial insemination protocols in postpartum dairy cows

Peripheral progesterone (P4) concentrations as well as pregnancy rates (PR) between cows treated with Ovsynch or CIDR ovulation synchronization/TAI protocols were compared. Two hundred and twenty-seven postpartum lactating Holstein cows were randomly assigned to Ovsynch (n = 111) or CIDR (n = 116) ovulation synchronization/TAI protocols. Pregnancy was diagnosed by ultrasonography at day 35 after TAI and later confirmed by rectal palpation at day 60 post TAI. Milk samples were taken from the beginning of treatment (day -10) until day 35 after TAI (day 0) for P4 determination. Pregnancy rates for Ovsynch and CIDR groups of cows were 31 and 41%, respectively. The PR of ovulation synchronized cows for Ovsynch and CIDR groups were 49 and 69%, respectively. Progesterone levels during the sampling period were similar (P &gt; 0.05) between Ovsynch and CIDR treated cows. Key words: Pregnancy rate, progesterone, Ovsynch, CIDR, cows

42 PREPARTUM HORMONAL CHANGES IN RECIPIENT COWS FOR SOMATIC CELL CLONED FETUSES

Placental estrogens are associated with fetal growth and development, and play important roles in the initiation of the parturition process. In the delivery of somatic cell-cloned (SC) calves, recipient cows show a weak and unclear symptom of parturition, although large offspring syndrome (LOS) frequently occurs. The mortality of calves by dystocia decreases the efficiency of SC cattle production. In this study, we examined peripheral estrone (E1), estradiol-17� (E2), estrone sulfate (E1S), and progesterone (P4) levels during preparturition in recipients of SC and in vivo calves. Recipients were administered 20 mg dexamethasone (DEX) at Days 276-288 of pregnancy, followed by 0.75-1 mg cloprostenol (PG) and 20 mg estriol 24 h later. Calves (Japanese black cattle) were delivered 2 or 3 days after the DEX administration. SC calves were delivered by cesarean section (C-sec) when LOS was suspected by rectal palpation. Blood samples of recipients [vaginal delivery of SC (Vag): n = 13; C-sec of SC: n = 8; vaginal delivery of in vivo calves (Control): n = 4] were taken at Days 257 and 271 of pregnancy, and just before DEX (-2P), PG (-1P), and parturition (0P). Blood samples of calves were taken just after delivery to analyze cortisol level. The statistical significance was analyzed by the Steel-Dwass test. Birth weight of calves was the heaviest (P &amp;lt; 0.05) in C-sec (62 � 3 kg; n = 12); Vag calves (43 � 2 kg; n = 19) were also heavier (P &amp;lt; 0.05) than Control calves (29 � 2 kg; n = 9). E1 levels in Control calves remained low (&amp;lt;629 � 111 pg mL-1) until Day 271 and then increased progressively (&amp;gt;2156 � 599 pg mL-1). E1 levels tended to be lower in Vag (&amp;lt;1968 � 299 pg mL-1) and C-sec (&amp;lt;1268 � 385 pg mL-1) calves at -2P, -1P, and 0P; E1 levels in C-sec calves were significantly lower (P &amp;lt; 0.05) than in Control calves at -2P (512 � 85 pg/mL-1) and -1P (725 � 91 pg mL-1). The E2 level in Control calves increased and reached a plateau at -2P. Vag and C-sec calves showed lower E2 levels, except that the Vag level at 0P was similar to that in Control calves. The E2 level of C-sec calves (61.8 � 25.3 pg mL-1) at 0P was significantly lower (P &amp;lt; 0.05) than that of Control calves (247.5 � 102.8 pg mL-1). E1S levels in Vag and C-sec calves increased progressively from -2P to 0P, whereas the E1S level in Control calves increased at 0P. The E1S level in Vag calves (41.1 � 4.1 ng mL-1) was significantly higher (P &amp;lt; 0.05) than in Control calves (19.4 � 5.1 ng mL-1) at -1P. P4 levels decreased from -2P in Vag and Control calves, and from -1P in C-sec calves. The cortisol level in C-sec calves (60.1 � 19.1 ng mL-1) tended to be low compared with that in Vag (104.4 � 23.1 ng mL-1) and Control (93.4 � 15.0 ng mL-1) calves. This study revealed fetoplacental dysfunction of estrogen synthesis in the SC fetus during preparturition. Elevated E1S levels in recipients of the SC fetus, which correlated with high birth weight and agreed with previous reports for normal or plural pregnancy, might cause the reduction of E1 level. The comparable level of cortisol in Vag and Control calves indicated that SC calves had normal adrenal cortex function. Further analysis on placental estrogen synthesis and cortisol secretion in the SC fetus is necessary to clarify the cause of the prolonged gestation.

Mechanisms Underlying “Functional” Progesterone Withdrawal at Parturition

Progesterone is a major factor maintaining uterine quiescence throughout pregnancy. In most species, peripheral progesterone levels decline before initiation of labor, and treatments that inhibit progesterone synthesis or action cause termination of pregnancy and/or premature deliveries. These findings suggest that progesterone withdrawal is required for activation of myometrial contractions. However, in humans, circulating progesterone levels remain elevated until birth, which leads to the notion that a "functional" progesterone withdrawal occurs before parturition. The apparent loss of progesterone sensitivity at term could be a consequence of several different mechanisms including: (1) the catabolism of progesterone in the uterus into inactive compounds; (2) alterations in progesterone receptor (PR) isoform ratios; (3) changes in cofactor protein levels affecting PR transactivation; and (4) inflammation-induced trans-repression of PR by nuclear factor kappaB. All of these mechanisms are potentially capable of decreasing uterine progesterone responsiveness at term, thus enabling the expression of pathways that originally were blocked by progesterone in early pregnancy. However, the specific uterine genes whose transcription is directly controlled by PR, and thus affected by "functional" progesterone withdrawal, remain to be identified.

Expression of matrix metalloproteinases and their tissue inhibitors in ovaries of senescence accelerated mice

We have shown that some corpora lutea (CLs) were abnormally accumulated in the ovaries of female SAMP1 mice. No significant differences in peripheral blood levels of progesterone or 17β-estradiol during estrus cycle were noted between SAMP1 and control-SAMR1 mice, and high activity of 20α-hydroxysteroid dehydrogenase was detected only in abnormally accumulated CLs (aaCLs) of SAMP1 mice. In the ovaries of SAMP1 mice, structural regression is inhibited in aaCLs, but functional regression does occur. In this study, we focused on the matrix metalloproteinases (MMPs) and tissue inhibitors of MMP (TIMPs), regulators of angiogenesis and angiodegeneration. In situ zymography (FIZ), terminal deoxynucleotidyl transferase-mediated biotinylated deoxyuridine triphosphate nick end-labeling (TUNEL) staining and histochemistry for hydroxysteroid dehydrogenases revealed that many TUNEL-positive apoptotic cells in regressing CLs of both SAMR1 and SAMP1 mice, but no apoptotic cells, were demonstrated in aaCLs of SAMP1 mice. MMPs and their mRNAs were detected in all ovaries of both SAMR1 and SAMP1 mice. In the murine ovaries, negative/trace activity of non-MMP proteinases was detected by FIZ techniques. Moderate/strong activities of MMPs were demonstrated in CLs of SAMR1 mice and in regressing CLs of SAMP1 mice, but trace MMP activity was noted in aaCLs of SAMP1 mice.

Olanzapine and clozapine increase the GABAergic neuroactive steroid allopregnanolone in rodents.

The neuroactive steroid allopregnanolone is a potent gamma-aminobutyric acid type A (GABA(A)) receptor modulator with anxiolytic and anticonvulsant effects. Olanzapine and clozapine also have anxiolytic-like effects in behavioral models. We therefore postulated that olanzapine and clozapine would elevate allopregnanolone levels, but risperidone and haloperidol would have minimal effects. Male rats received intraperitoneal olanzapine (2.5-10.0 mg/kg), clozapine (5.0-20.0 mg/kg), risperidone (0.1-1.0 mg/kg), haloperidol (0.1-1.0 mg/kg), or vehicle. Cerebral cortical allopregnanolone and peripheral progesterone and corticosterone levels were determined. Adrenalectomized animals were also examined. Both olanzapine and clozapine increased cerebral cortical allopregnanolone levels, but neither risperidone nor haloperidol had significant effects. Olanzapine and clozapine also increased serum progesterone and corticosterone levels. Adrenalectomy prevented olanzapine- and clozapine-induced elevations in allopregnanolone. Allopregnanolone induction may contribute to olanzapine and clozapine anxiolytic, antidepressant, and mood-stabilizing actions. Alterations in this neuroactive steroid may result in the modulation of GABAergic and dopaminergic neurotransmission, potentially contributing to antipsychotic efficacy.

Influence of the peripheral progesterone level on uterine distension during hysteroscopy in the horse

Influence of the peripheral progesterone level on uterine distension during hysteroscopy in the horse

Artificial Intravaginal Insemination Using Fresh Semen in Cats.

To clarify the sperm count required for fertilization by artificial intravaginal insemination (AIVI), twenty-nine female cats were examined. Six male cats aged 2-12 years with normal semen quality, copulation capability, and fertility were used. In AIVI, animals received administration of 250 iu hCG once or 100 iu twice on days 2-4 of estrus to induce ovulation, and were inseminated 15, 20, or 30 hr after the initial hCG administration. The success of ovulation was judged by elevation of the peripheral progesterone level after hCG administration. AIVI was investigated at three sperm counts, 20 x 10(6) (Experiment 1), 40 x 10(6) (Experiment 2), and 80 x 10(6) (Experiment 3), with semen collected by the artificial vagina method. Semen was infused in the vagina under general anesthesia by advancing a 9 cm-long nylon probe with 1.5 mm diameter connected to a 1 ml syringe in the vagina for 3-4 cm. Ovulation was induced in 43 of 45 animals (95.6%). One of 16 animals was fertilized (conception rate: 6.6%) by AIVI in Experiment 1. In Experiments 2 and 3, conception was obtained in six of 18 animals (33.3%) and seven of nine animals (77.8%), respectively, and the mean numbers of kits were 4.0 +/- 0.4 and 3.3 +/- 0.5, respectively, and the mean numbers of kits were 4.0 +/- 0.4 (SE) and 3.3 +/- 0.5, respectively, showing no significant difference. There were no differences in the time of insemination after hCG administration and the conception rate among these groups. Our findings showed that the number of sperm required for fertilization by AIVI of fresh semen in cats was 80 x 10(6).

避妊手術後に発情回帰した猫の血中性ステロイドホルモン値

Four cats showing the estrous signs and behaviour after ovariohysterectomy were examined for the peripheral levels of estradiol-17β and progesterone by RIA during and after estrus. The changes of both steroid levels in all the cases examined were similar to those in normal female cats. In one case treated with human chorionic gonadotrophin (hCG) and chlormadinone acetate (CMA), the estrous behaviour was effectively controlled.