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1.
It has been reported that ipriflavone was primarily metabolized via hepatic microsomal cytochrome P450 (CYP) 1A1/2 and 2C11 in rats, and the expression of hepatic CYP1A2 and 2C11 was not changed in rats with water deprivation for 72h compared to controls. Hence, it could be expected that the time-averaged nonrenal clearance (Cl(nr)) of ipriflavone would be comparable between two groups of rat. As expected, after intravenous administration of ipriflavone (20 mg/kg), the Cl(nr) values of ipriflavone were comparable between two groups of rat. This could be supported by comparable in vitro intrinsic clearance (Cl(int)) values for the disappearance of ipriflavone in hepatic microsomes for both groups of rat. After oral administration of ipriflavone (200 mg/kg), the total area under the plasma concentration-time curve from time zero to the last measured time, 12h, in plasma (AUC(0-12h)) values of ipriflavone were also comparable between two groups of rat. The above data suggest that dehydration state did not affect significantly pharmacokinetics of ipriflavone in rats. 相似文献
2.
Kaneko K Aoki H Furuichi T Hatori S Tanimoto H Kawakami S 《The Journal of reproduction and development》2004,50(3):361-367
To investigate how uterine inflammation affects ovarian activity in rats, endometritis was induced and changes in the length of estrous cycle and serum concentrations of estradiol-17beta (E(2)) and progesterone (P(4)) were examined. A suspension of Staphylococcus aureus (bacterial solution) or iodine solution was infused into the uterine lumen at various estrous phases. When the bacterial solution was infused at estrus, metestrus, or the first day of diestrus, the following diestrus continued for 5 to 12 days. In the case of the iodine solution, regardless of the estrous phase of the infusion, the following diestrus continued for approximately 6 days. E(2) concentration after infusion of each solution did not fluctuate largely and remained at a low concentration (around 5 pg/ml). P(4) concentration was high (35-45 ng/ml) on the day following infusion, but decreased rapidly to base line values within a few days and remained thereafter at a low level (around 5 ng/ml). It is assumed that the endometritis caused by biological or chemical stimulation raises the concentration of P(4) to depress gonadotrophic hormone secretion, and hence this high P(4) concentration might inhibit the growth of ovarian follicles. 相似文献
3.
Murakami Y Otsuki M Kusumoto K Takeuchi S Takahashi S 《The Journal of reproduction and development》2005,51(5):639-647
Interleukin-18 (IL-18) is a proinflammatory cytokine expressed in female reproductive organs in humans, rats and mice. The physiological roles of uterine IL-18 and the regulatory mechanisms of IL-18 gene expression are unclear. The present study aimed to clarify the effects of estradiol-17beta (E2) and progesterone (P4) on IL-18 mRNA expression in the mouse uterus. Distribution and expression levels of IL-18 mRNA were studied using an RNase protection assay. Expression of IL-18 mRNA was observed in all organs studied, including testes, ovaries and uteri. The uterine IL-18 mRNA level of estrous mice was higher than that of diestrous mice. E2 treatment (1, 5, 25 or 250 ng/mouse) decreased uterine IL-18 mRNA levels in ovariectomized mice dose-dependently. E2 treatment acutely decreased IL-18 mRNA levels 3 h after injection, but these levels returned to the initial level after 48 h. P4 treatment (1 mg/mouse) decreased uterine IL-18 mRNA levels after 12 h, but levels returned to the initial level after 48 h. Both uterine IL-18 and IL-18Ralpha mRNAs were detected in cultured endometrial epithelial and stromal cells. These results suggest that uterine IL-18 expression is reduced by sex steroid hormones and that IL-18 acts on endometrial cells in a paracrine or autocrine manner. 相似文献
4.
Sexually mature gilts (n = 20) were actively immunized against GnRH. Primary and booster immunizations of GnRH conjugated to bovine serum albumin induced production of antibodies in all gilts. Nineteen of the gilts became acyclic with suppressed concentrations of gonadotropins and estradiol. Intravenous challenges with 100 micrograms GnRH and 5 micrograms D-(Ala6, des-Gly-NH2(10)) ethylamide GnRH (a GnRH agonist that did not cross-react with antibodies produced by the gilts) caused release of LH and FSH, indicating maintenance of secretory capacity of pituitary gonadotropes in the immunized animals. Gilts were given 100 ng GnRH agonist at 2-h intervals for 72 h (n = 4) or 144 h (n = 10) or did not receive agonist (n = 5). Blood samples were taken every 6 h, and detectable concentrations of LH were observed in 42% and 52% of samples taken from gilts treated with or without agonist. In contrast, serum concentrations of FSH and estradiol were undetectable. Reproductive tracts and anterior pituitaries were taken from gilts at the conclusion of pulsatile administration of GnRH agonist or at 144 h for controls. Pituitary concentration of LH and FSH, uterine wet and dry weight, and size of the uterus were similar among groups. Paired ovarian weights for treated gilts pulsed with GnRH agonist for 72 h were heavier (P less than .05); however, ovaries from all immunized gilts were atrophied without follicular structures.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
5.
Kim SS Lee RD Lim KJ Kwack SJ Rhee GS Seok JH Lee GS An BS Jeung EB Park KL 《The Journal of reproduction and development》2005,51(2):201-210
Many environmental chemicals including pesticides have been reported to possess hormonal activities, and thus are classified as endocrine disruptors. Permethrin, a synthetic pyrethroid insecticide, is used worldwide, which provides potential environmental exposure. However, relatively few studies have reported on hormonal activities, particularly estrogenic and androgenic activities of permethrin, and the results of these studies are in some respects contradictory. Therefore, this study investigated the potential estrogenic and androgenic activities of permethrin in vitro and in vivo. We conducted an uterine Calbindin-D9k (CaBP-9k) gene expression assay and an uterotrophic assay for estrogenic activity, and a Hershberger assay for androgenic activity. The CaBP-9k gene, one of the intracellular calcium binding proteins, is estrogen-responsive in the uterus. The rat uterotrophic and Hershberger assays are generally used as in vivo short-term screening assays for detecting the estrogenic and androgenic activities of chemicals, although these assays are still being validated by the Organization for Economic Cooperation and Development (OECD). Northern blot analysis showed the induction of uterine CaBP-9k mRNA level in response to permethrin as well as co-administration of permethrin with E2. In the uterotrophic assay using 18-day-old female rats, subcutaneous treatments with permethrin (10 to 800 mg/kg) for three days increased relative uterine wet weights, and E2-induced uterine weights. These effects were statistically significant at 800 and 200 mg/kg, respectively. Moreover, permethrin-induced uterine weights were inhibited by the co-administration of ICI 182,780, an antiestrogen. In the Hershberger assay, the administration of permethrin orally to testosterone propionate-treated castrated male rats led to statistically significant reductions in androgen-dependent sex accessory tissue (ventral prostate, seminal vesicles, levator ani and bulbocavernosus muscles, Cowper's gland and glans penis) weights at all doses tested (10, 50 and 100 mg/kg). These results suggest that permethrin might have estrogen-like effects on female rats, but antiandrogen-like effects on males. 相似文献
6.
Lingfa KONG Quanwei WEI Jaafar Sulieman FEDAIL Fangxiong SHI Kentaro NAGAOKA Gen WATANABE 《The Journal of reproduction and development》2015,61(3):219-227
Thyroid hormones and oxidative stress play significant roles in the normal functioning of the female reproductive system. Nitric oxide (NO), a free radical synthesized by nitric oxide synthases (NOS), participates in the regulation of thyroid function and is also a good biomarker for assessment of the oxidative stress status. Therefore, the purpose of this study was to investigate effects of thyroid hormones on uterine antioxidative status in young adult rats. Thirty immature female Sprague-Dawley rats were randomly divided into three groups: control, hypothyroid (hypo-T) and hyperthyroid (hyper-T). The results showed the body weights decreased significantly in both the hypo-T and hyper-T groups and that uterine weights were decreased significantly in the hypo-T group. The serum concentrations of total triiodothyronine (T3) and thyroxine (T4), as well as estradiol (E2), were significantly decreased in the hypo-T group, but increased in the hyper-T group. The progesterone
(P4) concentrations in the hypo- and hyperthyroid rats markedly decreased. Immunohistochemistry results provided evidence that thyroid hormone nuclear receptor α/β (TRα/β) and three NOS isoforms were located in different cell types of rat uteri. The NO content and total NOS and inducible NOS (iNOS) activities were markedly diminished in the hypo-T group but increased in the hyper-T group. Moreover, the activities of both glutathione peroxidase (GSH-Px) and catalase (CAT) exhibited significant decreases and increases in the hypo-T and hyper-T groups, respectively. The malondialdehyde (MDA) contents in both the hypo-T and hyper-T groups showed a significant increase. Total superoxide dismutase (T-SOD) activity in the hypo- and hyper-T rats markedly decreased. In conclusion, these results indicated that thyroid hormones have an important influence on the modulation of uterine antioxidative status. 相似文献
7.
Progesterone plays important roles in the regulation of female reproduction. In this study, progesterone receptor (PR) mRNA levels in rat uterus during pregnancy, labor, lactation and the estrous cycle were examined by competitive RT-PCR. During pregnancy and lactation, PR mRNA levels had decreased on day 20 of pregnancy (P20) and P21 compared with P15 but increased during labor. After a decline on day 1 of lactation (L1), PR mRNA levels had increased again on L3 and L14 compared with P15, P18, P20, P21 and P21pm (at 2200-2300 h on P21). There was no significant change in the PR mRNA level during the estrous cycle. The PR mRNA level did not change during 1 week of progesterone treatment or afterwards. Injection of 17beta-estradiol did not affect PR mRNA levels in rats treated with progesterone or those without any injections. In rats on P18, 17beta-estradiol injection did not change PR mRNA levels after sham-operation but induced an increase in PR mRNA levels of rats ovariectomized 6 h before the treatment. These results suggest that uterine PR mRNA levels are differently regulated during late pregnancy, labor and lactation, and during labor estrogen is one of the essential factors for the increase in PR mRNA levels. 相似文献
8.
试验旨在研究血根碱对大鼠离体子宫平滑肌活动的影响。分离8周龄SD雌性未孕大鼠子宫平滑肌,通过BL-420F生物信号采集系统记录子宫平滑肌收缩频率和收缩幅度,计算子宫平滑肌活力。以硫酸阿托品、盐酸普萘洛尔、盐酸苯海拉明及盐酸雷尼替丁为阻断剂,观察血根碱对子宫平滑肌M、β、H1、H2受体的关系,探讨血根碱对子宫平滑肌的作用机制。结果显示,血根碱组和元胡止痛片组对缩宫素所致大鼠离体子宫平滑肌收缩频率、收缩幅度和活力均有显著的抑制作用（P<0.05）;应用H1受体阻断剂苯海拉明和H2受体阻断剂雷尼替丁后,血根碱对子宫平滑肌抑制作用基本被阻断,而应用M受体阻断剂阿托品,β受体阻断剂普萘洛尔后,血根碱对子宫平滑肌收缩仍具有显著的抑制作用（P<0.05）。综上所述,血根碱对大鼠子宫平滑肌活力具有显著的抑制作用,可能是通过抑制H1、H2受体实现,与M、β受体无关。 相似文献
9.
JIA Hai-yan XU Wan-qing ZHANG Ting-hua GAO Hui-qian WANG Li-fang WANG Hui 《中国畜牧兽医》2017,44(7):2209-2213
The study was aimed to explore the effects of the sanguinarine on activity of isolated rat uterine smooth muscle in vitro. The effect of the sanguinarine on activity of the isolated myometrium of non-pregnant Sprague-Dawley rats eight weeks old was recorded by BL-420F four channels physiological recorder. Four antagonists, atropine sulfate, ranitidine hydrochloride, propranolol hydrochloride and diphenhydramine hydrochloride were used to study their mechanism, respectively. The results showed that sanguinarine and Yuan hu painkillers markedly inhibited the frequency, amplitude and activity of uterine contractions induced by oxytocin injection (P<0.05). The inhibitory effect of sanguinarine on uterine muscle contractions was blocked after using diphenhydramine hydrochloride (H1-receptor antagonist) and ranitidine hydrochloride (H2-receptor antagonist). However, after using atropine sulfate (M-receptor antagonist) and propranolol hydrochloride (β-receptor antagonist), sanguinarine also significantly inhibited the contractions of rat uterine smooth muscle (P<0.05). It was concluded that the effect of sanguinarine on activity of uterine smooth muscle in rats was mainly associated with H1 receptor or H2 receptor but not M receptor or β receptor. 相似文献
10.
The objective of the present study was to determine the temporal relationships among luteal adenylate cyclase activity, luteal phosphodiesterase activity, luteal progesterone concentration and plasma progesterone concentration during prostaglandin F2 alpha (PGF2 alpha)-induced luteolysis in ewes. Corpora lutea (CL) were removed from cycling ewes on d 9 (d 0 = first day of estrus) at 0, 2, 4, 6, 12 and 24 h (seven to eight ewes/group) after PGF2 alpha administration (im). Jugular blood samples were collected at the time of enucleation of CL and analyzed for progesterone. Plasma and luteal progesterone concentrations were decreased (P less than .05) by 4 and 12 h after PGF2 alpha injection, respectively. Basal adenylate cyclase, luteinizing hormone (LH)-activated adenylate cyclase, guanylylimidodiphosphate [Gpp(NH)p]-activated adenylate cyclase and LH plus Gpp(NH)p-activated adenylate cyclase activities were decreased (P less than .05) by 2 h after PGF2 alpha injection. The decrease in adenylate cyclase activity paralleled the decrease in plasma progesterone concentration over time. Luteinizing hormone stimulated (P less than .05) adenylate cyclase activity relative to basal activity at 0, 2, 12 and 24 h post-PGF2 alpha; whereas, Gpp(NH)p stimulated (P less than .01) adenylate cyclase activity relative to basal activity at each time point. In contrast to the decrease in adenylate cyclase activity, phosphodiesterase activity was increased (P less than .05) at 2 and 4 h post-PGF2 alpha. These results suggest that a decrease in adenylate cyclase activity coupled with an increase in phosphodiesterase activity may decrease the intracellular adenosine 3',5' cyclic monophosphate (cAMP) concentration.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
11.
为了探索鹿角盘（DHAB）水提物对大鼠乳腺增生的治疗作用,初步探讨其作用机理和用药剂量,试验利用苯甲酸雌二醇（0.5 mg/（kg·d））联合黄体酮（5.0 mg/（kg·d））对SD大鼠进行肌内注射建立乳腺增生模型。试验共分7个组,每组10只大鼠,分别为空白组、乳腺增生症（HMG）模型组、阳性药三苯氧胺组（0.036 mg/（kg·d））、鹿角盘水提物4个剂量组（高剂量,2.625 g/（kg·d）;中高剂量,1.575 g/（kg·d）;中低剂量,1.05 g/（kg·d）;低剂量,0.63g/（kg·d））。按组别连续灌胃45 d,每周固定时间测定大鼠乳头直径、高度及体重。试验结束后采血取样,称量大鼠胸腺、脾脏、子宫和卵巢质量,取乳腺组织做病理学切片、HE染色,用放射免疫法检测大鼠血清中雌二醇（E2）及孕酮（P）的含量。结果表明,使用不同剂量鹿角盘水提物均能减小乳腺增生大鼠乳头直径、高度,提高胸腺、脾脏指数,降低子宫指数,减轻乳腺小叶数、腺泡数和分泌物,降低血清E2含量,升高血清P的含量,与模型组相比有统计学差异（P < 0.01;P < 0.05））。综合试验结果,鹿角盘水提物对乳腺增生大鼠有治疗作用,效果显著,且以中高剂量组变化最为明显。其作用机制可能通过增强机体免疫力、调节血清中E2、P水平实现。 相似文献
12.
Vascular effects of ergovaline mediated by 5-hydroxytryptamine(HT)2A, 5-HT1B/1D, and alpha1 receptors were studied in isolated arterial preparations of rat and guinea pig. In rat tail artery ergovaline behaved as a potent contractile partial agonist showing an agonist potency (pEC50) of 8.86 +/- 0.03, a maximum response (Emax) of 59 +/- 2% with respect to 5-HT, and a partial agonist affinity (pK(P)) of 8.51 +/- 0.06. Ergovaline was equipotent with ergotamine (pEC50, 8.69 +/- 0.07; Emax, 52 +/- 4%; pK(P), 8.36 +/- 0.11). Contractile responses to ergovaline and ergotamine were surmountably antagonized by the 5-HT2A receptor antagonist ketanserin (3 nM). Antagonist affinity (apparent pA2) for ketanserin against ergovaline and ergotamine was 9.19 +/- 0.08 and 9.36 +/- 0.17, respectively. Ergovaline showed extremely slow on-set and off-set kinetics in rat tail artery. The construction of cumulative concentration-response curves required about 4 h, and the contractile response to ergovaline (30 nM), which completely abolished the subsequent contractile response to 5-HT (10 nM to 1 mM), could not be reversed by wash-out. In guinea pig iliac artery moderately precontracted with prostaglandin F2alpha (0.05 to 0.5 microM) ergovaline behaved as an agonist (pEC50, 7.71 +/- 0.10) with a potency similar to that of 5-HT (pEC50, 7.60 +/- 0.05). The contractile response to ergovaline was inhibited by the 5-HT1B/1D receptor antagonist GR127935 (10 nM). The apparent pA2 value for GR127935 against ergovaline was 8.90 +/- 0.12. Ergovaline (10 nM) produced no contractile response in guinea pig iliac artery when added before the PGF2alpha-induced precontraction but caused insurmountable blockade of the contractile response to the 5-HT1B/1D receptor agonist 5-carboxamidotryptamine (5-CT). The apparent pA2 value for ergovaline against 5-CT was 8.56 +/- 0.18. In rat thoracic aorta ergovaline (2 microM) activated alpha1 adrenoceptors only with low efficacy (Emax, 12 +/- 3%) but surmountably antagonized norepinephrine-induced contractions with a pK(P) of 7.07 +/- 0.12. It is concluded that the powerful constrictor effect of ergovaline mediated by activation of vascular 5-HT2A and 5-HT1B/1D receptors may explain the vascular symptoms of fescue toxicosis observed in livestock grazing tall fescue pastures infected with the endophytic fungus Neotyphodium coenophialum. 相似文献
13.
Hojo T Ohno R Shimoda M Kokue E 《Journal of veterinary pharmacology and therapeutics》2002,25(2):121-127
In dogs effects of phenobarbital (PB) on hepatic cytochrome P450 (CYP) activities and on concentrations of plasma alpha 1-acid glycoprotein (AGP) were examined. Total body clearance (Cl(B)) of antipyrine and plasma AGP concentrations were monitored during oral PB treatment at a therapeutic dose for 35 days. Cl(B) of antipyrine, which reflects hepatic CYP activities, gradually increased and was maintained at about threefold concentrations compared with that before treatment, suggesting that PB induced CYP activities at a large extent even in a therapeutic dose, necessary for an antiepileptic effect. Plasma AGP concentrations also increased significantly (about fourfold). Dogs were killed at the 35th day of the PB treatment, and hepatic CYP content and enzyme kinetics of several CYPs were determined using liver microsomes. CYP content was about twofold higher than that from untreated dogs. The V(max) values for CYP1A-like activity (ethoxyresorufin O-deethylation), 2B-like activity (ethoxycoumarin O-deethylation), 2C-like activity (tolbutamide hydroxylation) and 3A-like activity (midazolam 4-hydroxylation) were higher (2-4-fold) than that in untreated dogs. In summary, a therapeutic dose of PB for antiepileptic therapy significantly induced hepatic CYPs and plasma AGP in dogs. Therefore, during antiepileptic therapy with PB, special attention must be paid to the pharmacokinetics of drugs simultaneously administered. 相似文献
14.
The secretion of ovine lymphocyte suppressor factor from jugular vein (JV), uterine vein (UV), and curetted hemopoietic uterine luminal (UL) mononuclear cells was evaluated on d 14 of the cycle, following ovariectomy (OVX) and after 14 d of progesterone injections (OVX + P4, 1 mg/kg BW). Mononuclear cells (predominantly lymphocytes) were harvested by Ficoll-Paque and placed into culture (2.5 x 10(6).mL-1.well-1 in RPMI-1640). Cellular supernatants were obtained at 72 h and volumes (5 to 50 microL) were tested for suppression of phytohemagglutinin (PHA [.08 microgram l)-treated peripheral blood lymphocytes (1.0 x 10(5)). In a concurrent experiment, PHA-treated JV, UV, and UL cells (1.0 x 10(5)) were cultured singly and JV cells (1.0 x 10(5)) were also cocultured with each of 1.0 x 10(5), 5.0 x 10(4), and 2.5 x 10(4) UV and UL cells. The incorporation of thymidine into DNA was quantified at 60 h. For the cellular supernatant experiment, thymidine incorporation was affected by reproductive phase (P less than .036), lymphocyte source (P less than .0001), and phase x source (P less than .004). For UL cells, the degree of suppressor activity follows: d 14 greater than OVX greater than OVX+P4 (P less than .05). The UL supernatant from OVX+P4-treated ewes and supernatants of JV and UV cells, irrespective of reproductive phase, lacked suppressor activity. Sephacryl S-200 chromatography revealed that UL supernatant from d-14 ewes contained a greater than or equal to 248,000 molecular weight suppressor macromolecule. For the cellular coculture experiment, thymidine incorporation was affected by reproductive phase (P less than .05) and lymphocyte source (P less than .0001).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
15.
Stability of glutathione peroxidase in swine plasma samples under various storage conditions. 
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下载免费PDF全文 The stability of plasma glutathione peroxidase under different temperatures (4 degrees C vs. -15 degrees C), various durations of storage (0, 1, 2, 3, 7, 14, 28 and 56 d), and storage under inert gas (nitrogen (N2)) vs air is described. The glutathione peroxidase activity of swine plasma decreased consistently with storage at either 4 degrees C or -15 degrees C 1-56 d after collection, and differed (P less than or equal to 0.01) from the initial values. Storage under N2 at -15 degrees C slowed the rate of enzyme activity decrease but did not maintain the initial activity. For absolute measurements, it is suggested that swine plasma glutathione peroxidase activity be measured immediately after separation from the blood cells or be assayed within 24 h in plasma samples stored at -15 degrees C with air space displaced by N2. If relative treatment differences in enzyme activity are satisfactory, then assays can be conducted after controlled periods of storage. 相似文献
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Taverne MA Breeveld-Dwarkasing VN van Dissel-Emiliani FM Bevers MM de Jong R van der Weijden GC 《Domestic animal endocrinology》2002,23(1-2):329-337
In the cow the foetal endocrine signals that initiate the calving process result in prepartum luteolysis. Withdrawal of progesterone (P4) action is a prerequisite for a normal calving. The rather abrupt declining influence of P4 is followed by a cascade of physiological processes in the myometrium and cervix. This contribution will focus on some of these events. Like in many other species, the myometrium in cows is not completely inactivated during pregnancy. So-called contractures have been registered during the final weeks of gestation and their EMG-characteristics in cows show a low frequency (on average: 13.6 per day) and long duration (on average 12.1 min). They are not evenly spread over the day because they occur less frequently when the cows are disturbed for feeding or cleaning their stables. Contractures affect several foetal functions. In the cow these contractures disappear during a period of about 8-9h when maternal plasma P4 levels are rapidly declining before calving. There is experimental evidence that this temporary inhibition is associated with prepartal luteal regression. The cause of this inhibition is still unknown. Because nitrous oxide inhibits smooth muscle cells and evidence in laboratory animals indicates that expression of the inducible form of nitrous oxide (iNOS) is downregulated in myometrium, but upregulated in the cervix around the onset of parturition, we started to investigate the role of this enzyme in bovine tissues around calving. By means of a RT-PCR technique, we obtained a first indication that iNOS is hardly expressed in the myometrium during calving, while expression was clearly detected at day 4 after calving. Analysis of prepartum en periparturient biopsies from myometrium and cervix with quantitative PCR is still underway. In six pregnant cows, provided with uterine EMG-electrodes and with ultrasonic crystals implanted on the caudal cervical rim to measure cervical dilatation, calving was induced with an injection of prostaglandin (PG) F2alpha. While maternal plasma P4 levels had significantly declined within 8h after PG treatment, the myometrium escaped from temporary inhibition with the development of a parturient contractility pattern on average at 13.5h after injection. However, it was only at 28 h after PG treatment that the first sustained increase of the opening of the vaginal ostium of the cervix was measured. 相似文献
18.
Kawai K Uetsuka K Doi K Nakayama H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2006,68(2):105-111
We conducted zymography for detecting the activity of matrix metalloproteinases (MMPs) and reverse zymography for the activity of tissue inhibitors of metalloproteinases (TIMPs) in canine spontaneous and rat 7, 12-dimethylbenz(a)anthracene (DMBA)-induced mammary tumor tissues. The activities of MMPs of canine mammary tumors were quite higher than those of the rat chemically induced tumors. The activities of MMPs were significantly higher in malignant tissues than in benign ones of canine tumors, whereas the activity of only MMP-2 was higher in both benign and malignant rat tumors compared to normal tissues. There were no differences of MMPs activities between benign and malignant rat tumors. The results of reverse zymography indicated that the activities of TIMP-1, -2 and -3 were strikingly higher in rat tumors than in canine tumors. The activities were higher in malignant tissues than in benign ones of dogs, and higher in tumor tissues than in normal mammary tissues of rats. The results of film in situ zymography for tissue localization of gelatinolytic activity showed that the digested area was more extended in malignant tumors than in benign ones of dogs. However, the area was similarly extended in both benign and malignant rat tumors. These results may indicate that the canine spontaneous malignant mammary tumors possess more aggressive nature than the rat chemically induced counterpart, resulting from the high level of MMPs and low level of TIMPs activities of the tumor tissues. 相似文献
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The effect of exogenous iron and folate on reproductive performance in swine is equivocal. However, the effect of exogenous iron and folate on secretion of their respective uterine transport proteins has never been reported. Twenty gilts were infused (n = 5 per treatment) with either 1) saline, 2) alpha-tocopherol, 3) alpha-tocopherol plus iron citrate, or 4) alpha-tocopherol plus tetrahydrofolate on d 11 to 14 of pregnancy. Intravenous infusion of iron citrate and tetrahydrofolate increased (P < 0.05) plasma iron and folate, respectively, for 6 to 8 h after treatment. Treatments had no effect on uterine content of uteroferrin or secreted folate-binding protein in uterine flushings obtained on d 15 of pregnancy. These data suggest that uterine secretion of uteroferrin and secreted folate-binding protein are not influenced by plasma levels of iron and folate, respectively, and may provide an explanation for the equivocal effect of iron and folate treatment on reproductive performance in gilts. 相似文献