In vitro liver clearance of tritiated estradiol-17β in the female rat after retrochiasmatic transection and ovariectomy

It was reported in a previous study that serum estradiol-17β (E₂) was elevated in rats after retrochiasmatic transection (FC). Serum E₂ was also higher in estradiol cypionate treated, ovariectomized (ovx) rats that had been subjected to FC than in those that had not. This suggested that increased secretion of E₂ was not the only factor responsible for elevated serum E₂ after FC. To ascertain the contribution of decreased metabolism of E₂ to this response, liver tissue slices were incubated with 3H-estradiol-17β, and the rates of ³h uptake and conversion to water-soluble conjugates were measured.The rate of uptake of ³H by the tissue was not indicative of the rate of conjugate formation. Livers of rats with high serum E₂ exhibited lower rates of ³h uptake than those of rats with low serum E₂. Even so, the formation of ³H conjugates was greater in liver of rats with high serum E₂. As hypothesized, livers of rats with FC formed conjugates at a significantly lower rate than those of similarly treated rats without FC. Thus, FC of an intact rat leads to an increase in serum E₂ by increasing the secretion of E₂, and apparently also by decreasing the rate of E₂ metabolism by the liver.     

Caprine endometrial stromal cells modulate the effects of steroid hormones on cytokine secretion by endometrial epithelial cells in vitro

The main purpose of this study was to examine the effects of 17β-estradiol (E₂) and progesterone (P₄) on cytokine secretion by caprine endometrial epithelial cells (EEC) in vitro. Epithelial cells grown alone or in co-culture with stromal cells (ESC) were treated with E₂ or P₄, or both. Homogeneity of the endometrial cell populations was ascertained immunocytochemically. The quantities of cytokines secreted in this system were assessed by ELISA and their protein expression by Western blot. The exposure of EEC to P₄ alone or in combination with E₂ significantly increased the amount of TGF-β1, TNF-α and IL-18 secretion, whereas E₂ had no effect on the synthesis of these cytokines. When epithelial cells were co-cultured with ESC, the secretion of TGF-β1, TNF-α and IL-18 by EEC significantly increased compared to that by EEC alone. However, the treatment with both steroids decreased the secretion of TNF-α, IL-18 and TGF-β1 by EEC in the presence of ESC. In contrast to TGF-β1, TNF-α and IL-18, the secretion of leukemia inhibitory factor (LIF) by EEC was not affected by E₂ and/or P₄ either directly or indirectly. The present results indicate that the interactions between caprine endometrial stromal and epithelial cells can modulate the secretion of TGF-β1, TNF-α and IL-18 by EEC exposed to E₂ and/or P₄ in vitro.     

Nicotine stimulates maturational gonadotropin (GtH2) release from carp (Cyprinus carpio L.) pituitary cells

1. Perifusion of dispersed pituitary cells and pituitary cell culture was used to investigate the effects of cholinergic drugs on the secretion of maturational gonadotropin (GtH₂) in carp.2. Nicotine strongly, and in a dose dependent manner, stimulated GtH₂ release in male and in female carp (from 10⁻⁸M in the Perifusion and 10⁻¹⁰M in the cells cultures).3. Nicotine is 10 times more active in females than in males.4. The results suggest that in carp, nicotine stimulates GtH₂ release directly from the pituitary cells, indicating a possible involvement of a cholinergic system in the regulation of GtH₂ secretion in teleost fish.     

Sialic acid binding protein of human endometrium: Its regulation by steroids

In the present study, we have observed that sialic acid binding protein (SABP – a 54 kDa glycoprotein which was isolated from human endometrial scrapings taken at various stages of the menstrual cycle from normal cycling females and purified to apparent homogeneity and was earlier reported from this laboratory) was found in sufficiently detectable amount in the endometrium of normal cycling women whereas it was found in lesser amount in tissue from women who have recently entered the post-menopause stage. SABP was observed in both follicular and luteal phase of menstrual cycle which was found by western blot analysis. In the de-novo synthesis experiment, synthesis and secretion of SABP was found to be stimulated by estradiol (E₂) whereas progesterone (P₄) was found to have no significant stimulatory effect on it which was also confirmed by HEC cell culture. In the HEC cell culture, priming of cells with E₂ was found to influence the effect of P₄ on SABP when it was added 2 h after E₂ administration. This was observed by doing immunoprecipitation followed by SDS-PAGE and autoradiography. Hence this report clearly indicates that E₂ regulates the synthesis and secretion of 54 kDa SABP from human endometrium. How E₂ priming of endometrium influences the effect of P₄ on SABP has been discussed.     

Mechanical asymmetry during articulation of tibial and femoral cartilages: Local and overall compressive and shear deformation and properties

During knee movement, femoral cartilage articulates against cartilage from the tibial plateau, and the resulting mechanical behavior is yet to be fully characterized. The objectives of this study were to determine (1) the overall and depth-varying axial and shear strains and (2) the associated moduli, of femoral and tibial cartilages during the compression and shearing of apposing tibial and femoral samples. Osteochondral blocks from human femoral condyles (FCs) characterized as normal and donor-matched lateral tibial plateau (TP) were apposed, compressed 13%, and subjected to relative lateral motion. When surfaces began to slide, axial (?E_zz) and shear (E_xz) strains and compressive (E) and shear (G) moduli, overall and as a function of depth, were determined for femoral and tibial cartilages. Tibial ?E_zz was ～2-fold greater than FC ?E_zz near the surface (0.38 versus 0.22) and overall (0.16 versus 0.07). Near the surface, E_xz of TP was 8-fold higher than that of FC (0.41 versus 0.05), while overall E_xz was 4-fold higher (0.09 versus 0.02). For TP and FC, ?E_zz and E_xz were greatest near the surface and decreased monotonically with depth. E for FC was 1.7-fold greater than TP, both near the surface (0.40 versus 0.24 MPa) and overall (0.76 versus 0.47 MPa). Similarly, G was 7-fold greater for FC (0.22 MPa) than TP near the surface (0.03 MPa) and 3-fold higher for FC (0.38 MPa) than TP (0.13 MPa) overall. These results indicate that tibial cartilage deforms and strains more axially and in shear than the apposing femoral cartilage during tibial–femoral articulation, reflecting their respective moduli.     

Effect of conceptus secretions on HOXA10 and PTGS2 gene expression, and PGE2 release in co-cultured luminal epithelial and stromal cells of the porcine endometrium at the time of early implantation

Homeobox A10 (HOXA10) gene expression was demonstrated in the endometrium of adult porcine uteri, however there is little information concerning the role of this gene in the pig. Objectives of the present study were to examine: 1) the expression of HOXA10 in the endometrium of cyclic and early pregnant gilts; 2) the effect of estradiol (E₂) and progesterone (P₄) on HOXA10 expression in porcine luminal epithelial (LE) and stromal (ST) cells in vitro; 3) the effect of E₂ and conceptus-exposed medium (CEM) on HOXA10 and prostaglandin endoperoxide synthase (PTGS2) gene expression and prostaglandin (PG) E₂ secretion from LE and ST cells in a co-culture model. The abundance of HOXA10 mRNA was increased on day 15 of pregnancy in comparison to day 15 of the estrous cycle. Moreover, increased HOXA10 mRNA level was detected in ST cells after E₂ and P₄ treatment. E₂ stimulated the expression of HOXA10 in LE cells cultured on collagen and pre-treated with steroids, but not in LE on plastic surfaces. Addition of CEM to LE cells cultured in collagen-coated inserts of the co-culture system resulted in elevated HOXA10 and PTGS2 gene expression and PGE₂ secretion in these cells, but not in ST cells cultured in basal compartments. ST cells directly treated with E₂ or CEM showed higher levels of HOXA10 and PTGS2 expression. Blocking of estrogen receptors with ICI-182,780 did not influence the stimulatory effect of CEM. We conclude that HOXA10 expression in the porcine endometrium is closely related to the implantation process and stimulated by conceptus products. Moreover, the co-culture system of LE and ST cells is a promising model for the study of endometrial response to conceptus-derived factors.     

Leptin controls rabbit ovarian function in vivo and in vitro: Possible interrelationships with ghrelin

The aim of these in vivo and in vitro studies was to examine the role of leptin in the control of plasma hormone concentrations, reproduction, and secretory activity of ovarian granulosa cells.In in vivo experiments, 15 female European domestic rabbit (Oryctolagus cuniculus) were treated with leptin (5 μg animal⁻¹ d⁻¹ for 1 wk before induction of ovulation with 25 IU equine chorionic gonadotropin and 0.25 IU human chorionic gonadotropin), and 15 females constituted the control group (treated with phosphate-buffered saline). Plasma concentrations of progesterone (P₄), testosterone (T), estradiol (E₂), estrone sulfate (ES), and insulin-like growth factor I (IGF-I) were determined at the estimated day of ovulation by radioimmunoassay (RIA), and number, viability, and body weight of newborns were recorded at parturition. In in vitro experiments, granulosa cells were isolated from periovulatory ovarian follicles of five control and five females treated with ghrelin (10 μg animal⁻¹ d⁻¹ for 1 wk before induced ovulation). Isolated cells were cultured for 2 d with and without leptin (0, 1, 10, or 100 ng/mL medium). Secretion of P₄, T, E₂, IGF-I, and prostaglandin F (PGF) was assessed in culture medium by RIA.In in vivo experiments, leptin administrations reduced plasma P₄, T, E₂, ES, and IGF-I levels. Leptin treatments did not affect ovarian weight or total number and body mass of newborns, but the proportion of pregnant females and number of live newborns were significantly higher in leptin-treated females than that in control females. In in vitro experiments, leptin significantly decreased (at 1 and 10 ng/mL) or increased (at 100 ng/mL) P₄ secretion, promoted E₂ and IGF-I (both at 100 ng/mL) secretion, and reduced T (at 1 and 10 ng/mL) and PGF (at 10 ng/mL) secretion. Granulosa cells from ghrelin-treated animals secreted less P₄, T, E₂, and PGF, but not IGF-I, than that secreted by granulosa cells from control animals. Furthermore, pretreatment of animals with ghrelin suppressed or even reversed subsequent leptin effects on P₄, T, E₂, IGF-I, and PGF secretion by cultured granulosa cells.These observations (1) show for the first time that leptin can increase the number of live newborns in rabbits, (2) confirm previous data on the ability of leptin to control ovarian secretory activity both directly and via upstream mechanisms, (3) demonstrate the involvement of ghrelin in the control of rabbit ovarian secretory functions, and (4) suggest an antagonistic interrelationship between leptin and ghrelin in the rabbit.     

Stimulation of the estrogen synthesizing system of the immature rat ovary by exogenous and endogenous gonadotropins

Immature rat ovaries increase their secretion of estradiol (E₂) when stimulated by gonadotropins but only after a lag period of several hours. Once established, estrogen secretion can be maintained, or increased, by the continued presence of gonadotropin. A combination of ovine FSH+LH given at 2 hr intervals stimulated the estrogen synthesizing system ($\text{ESS}$) of the ovary and serum E₂ showed a pronounced rise between 16 and 20 hrs after the initial injection. When given every 2 hrs for 5 doses (0–8 hrs) serum E₂ was undetectable. However, it was increased if 20 IU PMS was injected at the time of the last dose of FSH+ LH. Endogenous FSH&LH, increased by hourly injections of LH-releasing hormone for a period of 8 hrs, stimulated the $\text{ESS}$; serum E₂ increased at the expected time when this treatment was followed by an injection of PMS.Anti-PMS antiserum given 12 hrs after PMS, prevented the expected rise in serum E₂ at 24 hrs. However, FSH, LH or a combination of the two given every 2 hrs beginning at the time of the anti-PMS produced an increase in E₂ secretion; the combination was more effective than either hormone alone.These results are consistent with the interpretation that a combined FSH-LH action is responsible for induction of the $\text{ESS}$ in the immature rat ovary. The combination of hormones is also very effective in maintaining estrogen secretion but some function appears possible with FSH or LH alone.     

Steroids and gonadotropins during the late pre-ovulatory phase of the menstrual cycle. Time relationships between plasma hormones levels and luteinizing hormone surge onset

Four daily blood samples were collected during the late pre-ovulatory phase in 77 non-treated patients and in 18 clomiphene-treated patients. All hormonal events were dated by referring to the onset of the luteinizing hormone (LH) surge.LH basal level increased (P < 0.01) on the day preceding the LH surge onset whereas it was stable during the 4 preceding days. In most of the cycles the LH and FSH surges began at the same time (73%) and reached their peak at the same time (62%). The LH surge lasted about 30 h and its rising phase was of 13 h duration on average. The rise and the whole surge durations were found to be rather longer for the FSH than for the LH and peak values of both gonadotropins were higher when the respective LH (P < 0.02) and FSH (P < 0.01) rise durations were longer.In 55.8% of the cycles, the oestradiol (E₂) peak did not occur before the LH surge onset; a significant E₂ rise (P < 0.02) which preceded the E₂ peak was found between 35 to 30 h before the LH surge onset. No significant difference was found in androgen levels during the 2 days preceding the LH surge and the day which followed the LH surge onset. An increase of progesterone or 17-hydroxy-progesterone (17-OHP) was observed before the time of the LH surge onset in 30.0 and 80.0% of the cycles respectively.When individual results were combined over a 5 h time interval it appeared that the sequence of plasma hormone changes, in relation to the time of the LH surge onset, could be described as follows: E₂ rises at −30 h immediately before LH basal level increase at −24 h, then 17-OHP rises at -5 h and finally LH and FSH surges begin at time 0.     

Critical responses of photosynthetic efficiency of goldspur apple tree to soil water variation in semiarid loess hilly area

Goldspur apple (Malus pumila cv. Goldspur) is one of the main fruit trees planted in semiarid loess hilly areas. The photosynthetic efficiency in leaves of eight-year-old trees were studied under different soil water conditions with a Li-6400 portable photosynthesis system and a Li-Cor1600 portable steady state porometer in order to explore the effects of soil water stress on photosynthesis and the suitable soil water content (SWC) for water-saving irrigation of apple orchards. The results showed that the leaf net photosynthetic rate (P _N), transpiration rate (E), water-use efficiency (WUE), stomatal conductance (g _s), intercellular CO₂ concentration (C _i), and stomatal limiting value (L _s) displayed different threshold responses to soil water variation. When SWC was within a range of about 60%–86% of field capacity (FC), P _N and E were maintained in a relative steady state. At an elevated level but below 60% of FC, both P _N and E decreased evidently with decreasing soil moisture. The SWC needed to support WUE in a relatively steady state and at a high level was in the range of about 50%–71% of FC. When SWC was less than 48% of FC, g _s and L _s declined with decreasing soil moisture, while C _i increased rapidly. Based on the analysis of the stomatal limitation of photosynthesis using two criteria (C _i and L _s) suggested by Farquhar and Sharkey, it was implied that the predominant cause of restricting P _N had changed from stomatal limitation to nonstomatal one under severe water stress. In terms of water-saving irrigation for enhancing water-use efficiency, it was concluded that in semiarid loess hilly areas, the suitable range of SWC for water-saving irrigation in goldspur apple orchards is in the range of about 50%–71% of FC, and the most severe degree of soil water stress tolerated for photosynthesis is about 48% of FC.     

Hormonal regulation of sialic acid-binding (SAS) protein synthesis of rat uterus

Sialic acid binding proteins (SAS) of rat uteri have been found in all three stages of the estrous cycle. To study the control of synthesis of these proteins two different animal models were used I-immature female rats (25 d) where the hormones estradiol (E₂) and progesterone (P₄) were given separately and together, and II-adult female rats where hormone treatment commenced 14 days after ovariectomy. The data indicated that E₂ initiated the synthesis of SAS proteins in the immature animals, while P₄ could inhibit SAS synthesis, either given alone or together with E₂. However, prior priming of the rat with E₂ and subsequent administration of P₄ stimulated SAS protein synthesis.     

The Interaction Between Selenium Status, Sex Hormones, and Thyroid Metabolism in Adolescent Girls in the Luteal Phase of their Menstrual Cycle

The objective of the present work was to study all physiological relationships among selenium status (SeS), sex hormones secretion (SH), and thyroid metabolism (ThM) in healthy adolescent girls, at one time. Forty-four girls aged 13.4–16.6 years (mean age, 14.5 ± 0.5 years) entered the statistical model. Parameters reflecting SeS: plasma selenium concentration (Se) and plasma glutathione peroxidase activity (GPX3); SH: serum estradiol (E₂) and progesterone (P₄); age of menarche (AoM); and ThM: thyroid stimulating hormone (TSH), free thyroxine (fT4), free triiodothyronine (fT3), antithyroid peroxidase antibodies (anti-TPO) in serum, and thyroid volume (ThV), were determined, and the interactions between them were evaluated by means of the partial least squares method (PLS). PLS method was, for the first time, successfully applied to the problem of selenium and hormone interactions and revealed that selenium status and female reproductive system are interrelated and affect thyroid physiology in adolescent girls in the luteal phase. The strongest associations were revealed for the pairs of parameters, Se and fT4/fT3, Se and P₄, the modest ones for the pairs, Se and ThV, P₄ and fT4/fT3, Se and AoM, and P₄ and AoM. There was no correlation between E₂, GPX3, and TSH, and any other considered parameter. Se and P₄ had the greatest influence on ThM parameters.     

Non-lethal assessment of reproductive stage for female blue sharks Prionace glauca using sex steroid hormones

Plasma concentrations of progesterone (P₄) and 17β-oestradiol (E₂) in juvenile, pre-ovulatory, early, mid- or late pregnancy stages of female blue sharks Prionace glauca were analysed. Concentrations of P₄ were significantly higher in pregnant than in non-pregnant individuals, whereas E₂ concentrations increased with embryonic and follicular development. A highly accurate (86.1%) random forest classification model was developed to predict shark pregnancy. It is proposed that hormone concentrations could be used for the subsequent non-lethal determination of female P. glauca reproductive state.     

Plasma relaxin concentrations in the pig during the periparturient period: Association with prolactin,estrogen and progesterone concentrations

Concentrations of relaxin, prolactin, unchromatographed estradiol 17_β (E_2β) and progesterone (P₄) were measured in serial samples of inferior vena caval blood, in three pigs, during late pregnancy, and parturition. Maximal relaxin concentrations occurred 60 to 24h before parturition, and ranged from 60 to 286ng/ml. Prolactin concentrations increased from 12.5ng/ml, 48 to 36 hours before parturition, to between 79 to 184ng/ml. At the time of the relaxin surge, E_2β levels were high, and P₄ concentrations were decreasing, thus raising the $\text{E}{}_{\mathrm{2\beta }}\text{P}{}_4$ ratio. A surge in prolactin concentrations followed upon a decline of P₄ to less than 10ng/ml, coinciding with the increase in relaxin concentrations in 2 gilts, and following the surge in relaxin in the third. Udder development occurred near the time of increased relaxin concentrations. ‘Milk let down’ followed maximal relaxin and prolactin concentrations in two gilts, and the increase in prolactin, rather than the increase in relaxin concentration, in the third.     

元江鲤种群遗传多样性

选择12对微卫星标记检测了于2011年采集自元江(红河上游中国江段)5个样点192尾鲤的群体遗传多样性.共检测到201个等位基因,每个位点等位基因2-27个.各群体各位点平均等位基因(NA)12.25-14.67个,平均有效等位基因(NE)8.28-9.73个,平均观察杂合度(Ho)o.7765-0.8037,平均期望杂合度(HE)0.7761-0.8080,平均多态信息含量(PIC)0.7534-0.7843.元江鲤种群192个个体各位点NA、NE、Ho、HE、PIC分别为16.50、11.26、0.7927、0.8049、0.7966,种群遗传多样性水平高.元江鲤群体之间遗传分化小,可作为一个种群管理单元进行管理.增殖放流要防止遗传多样性丧失.     

Hormones and sexual behavior associated with postconception perineal swelling in the sooty mangabey (Cercocebus torquatus atys)

Three studies were conducted with female sooty mangabeys to describe the occurrence of perineal swelling during pregnancy and to document the associated patterns of ovarian hormone secretion and sexual behavior. Menstrual cycles and pregnancies were charted in 29 female subjects by recording daily vaginal bleeding and perineal swelling. As in other swelling species, maximum perineal tumescence corresponded with the periovulatory phase of the cycle; however, a second tumescence was recorded during pregnancy, with a peak at 49 days postconception. The swelling patterns were similar with the exception that deturgescence was slower during pregnancy. In a second study, blood samples were obtained weekly from nine females to document the estradiol (E₂) and progesterone (P₄) profiles during pregnancy. Analyses revealed increased E₂ concentrations and low P₄ levels in association with the postconception swelling. A third study compared sexual behavior during ovulatory and post-conception tumescent peaks. Behavioral data revealed that, although there was no overall difference in male mount rate to females during the ovulatory and postconception maximum swelling period, when only the alpha male was considered, significantly fewer mounts were directed to females exhibiting a post-conception versus an ovulatory maximum tumescence.     

Genistein protects ovarian granulosa cells from oxidative stress via cAMP‐PKA signaling

Genistein is an isoflavone that has estrogen (E₂)‐like activity and is beneficial for follicular development, but little is known regarding its function in oxidative stress (OS)‐mediated granulosa cell (GC) injury. Here, we found that after exposure to H₂O₂, Genistein weakened the elevated levels of intracellular reactive oxygen species (ROS) and malondialdehyde (MDA), which were regarded as the biomarkers for OS, and rescued glutathione (GSH) content and GSH/GSSG ratio accompanying with a simultaneous increase in cyclic adenosine monophosphate (cAMP) level, whereas addition of protein kinase A (PKA) inhibitor H89 impeded the effects of Genistein on the levels of ROS and MDA. Further analysis evidenced that Genistein enhanced the activities of antioxidant enzymes superoxide dismutase (SOD), GSH‐peroxidase (GSH‐Px), and catalase (CAT) in H₂O₂‐treated GCs, but this enhancement was attenuated by H89. Under OS, Genistein improved cell viability and lessened the apoptotic rate of GCs along with a reduction in the activity of Casp3 and levels of Bax and Bad messenger RNA (mRNA), while H89 reversed the above effects. Moreover, Genistein treatment caused an obvious elevation in mitochondrial membrane potential (MMP) followed by a decline in the levels of intracellular mitochondrial superoxide, but H89 inhibited the regulation of Genistein on MMP and mitochondrial superoxide. Supplementation of Genistein promoted the secretion of E₂ and increased the expression of Star and Cyp19a1 mRNA, whereas suppressed the level of progesterone (P₄) accompanied with a decline in the level of Hsd3b1 mRNA expression. H89 blocked the regulation of Genistein on the secretion of E₂ and P₄, and alleviated the ascending of Star and Cyp19a1 elicited by Genistein. Collectively, Genistein protects GCs from OS via cAMP‐PKA signaling.     

An integrated diagnostic approach to understand drought tolerance in mulberry (Morus indica L.)

Four popular mulberry cultivars (Morus indica L. cvs.V-1, MR-2, S-36 and K-2) were assessed for drought tolerance with an integration of selective approaches. The potted plants were subjected to two watering treatments for 75 days: control pots were watered up to 100% field capacity (FC) and stressed pots were maintained at 25–30% FC. Net photosynthetic rate (P_n), stomatal conductance (g_s), transpiration rate (E) and instantaneous water use efficiency (WUE_i) were the key parameters to assess photosynthetic gas exchange performance. Drought caused marked down-regulation in leaf gas exchange in all cultivars (cvs) except V-1 which maintained better P_n, g_s, E and higher WUE_i under severe water deficit. All the four cvs also showed differential antioxidative responses under water stress. Higher concentrations of carotenoids, ascorbic acid, glutathione, α-tocopherol and proline were observed in the leaf extracts of V-1, while minimum accumulation of those metabolites was recorded with K-2 and S-36. An endogenous loss of α-tocopherol and higher lipid peroxidation were encountered in K-2, S-36 and MR-2, whereas V-1 showed minimum lipid peroxidation under water deficit regimes. Comparative morpho-anatomical analysis revealed a well-developed root system and a better anatomical architecture in V-1 which could further contribute tolerance during drought stress.