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以雌性2~3岁小尾寒羊为试验动物,对其进行超数排卵,研究血清中NO含量对绵羊超数排卵的影响。结果表明:发情前期,绵羊试验组血清中NO含量(16.62±10.52)μmol/L显著高于对照组此时的含量(6.62±3.56)μmol/L(P<0.05);绵羊试验组的黄体数与第4次(注PG时)血清中的NO(9.03±3.39)μmol/L呈负相关(r=-0.670,P<0.05);可用胚数与第2次采血中的NO呈负相关(r=-0.764,P<0.05)。由此可知,在超排过程中,绵羊体内NO水平是变化的,并且随着卵泡的发育,NO的合成增加;发情前期NO与获胚数、可用胚数呈负相关,外周血中高水平的NO对发情前期的卵泡发育有消极影响。 相似文献
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大量研究表明,一氧化氮(NO)作为一种信息递质,可以调控卵泡发育、卵母细胞的成熟和排卵等生殖过程。近年来的研究表明,NO变化水平与超排效果有密切联系。国外有学者进行过小鼠超排与NO关系的研究,但有关NO水平对山羊超排影响的研究国内外至今未见报道。为此,试验对山羊超排过程 相似文献
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促卵泡激素(FSH)能够刺激有腔卵泡的继续生长和发育成熟,在母畜发情前期开始以减量法多次(6-8次)大剂量注射FSH可促进可能退化的卵泡发育成熟,其排卵数量可超过正常排卵数,可为牛、羊胚胎工程研究与生产应用中在有限的母畜获得大量胚胎提供了可能。由于FSH的生物学半衰期较短, 相似文献
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随着体外受精、克隆与转基因动物等基础研究快速发展,对卵母细胞的需求越来越多,科学家们不得不寻求能够获得大量优质卵母细胞的新途径。原始卵泡作为生长卵泡的来源,其初始容量影响哺乳动物的繁殖性能,是整个雌性生殖期中各阶段卵泡及卵子发育的源头。哺乳动物的卵巢在出生时由一定数量的卵泡组成,大多数原始卵泡处于休眠状态,只有极少数的原始卵泡被激活并进入生长卵泡池中。因此合理开发卵巢里尚未激活的原始卵泡对提高动物繁殖率、加速优良牛种的遗传改良、阐明动物卵泡发生的分子机理具有重要意义。本文将目前哺乳动物原始卵泡体外激活的国内外进展做一综述,为研究动物和人类卵泡激活的生物学过程提供理论基础。 相似文献
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1孕马血清促性腺激素
孕马血清促性腺激素是母马在怀孕的40~120天时子宫内膜产生的糖蛋白类激素。孕马血清促性腺激素的生物学作用类似于促卵泡激素。孕马血清促性腺激素的生物学半衰期较长,可达40~125小时,主要用于母畜催情和促进卵泡发育、超数排卵、 相似文献
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《中国兽医学报》2020,(9)
为寻找牛卵泡颗粒细胞(GCs)凋亡的关键调控因子,阐明单胎动物卵泡闭锁调控机理,本研究对奶牛优势卵泡与从属卵泡GCs深度测序,筛选卵泡发育相关的下调基因。选取健康荷斯坦奶牛,屠宰后,分别采集卵巢上正常发育的最大卵泡(8~10 mm)与第二大卵泡(5~8mm),并结合雌激素/孕激素确定卵泡优势与否,优势卵泡(DF):E_2/P1;从属卵泡(SF)E_2/P1。分别刮取GCs,提取总RNA并建库,Illumina测序,将获得序列与牛Refseq数据库比对后,利用DESeq2软件对获得的RNA进行差异表达分析,并对其中表达下调的基因进行GO和KEGG信号通路分析,最后通过Real-time PCR对筛选出的表达下调基因进行验证。测序共获得32 346个基因,其中194个在DF中表达显著上调,502个表达下调;GO分析结果显示,这些下调基因的生物学功能共分为3大类104组,其中生物学过程相关基因占61.5%,细胞组分有关基因占25.0%,分子功能相关基因占13.5%;KEGG信号通路分析,共发现5条通路,其中基因富集最为显著的是癌症通路;从下调基因中筛选出4个在牛卵泡发育过程中可能会起抑制作用的基因,QRT-PCR结果显示,PPP1R14A、QRFPR和EGR1在DF和SF中的表达趋势与深度测序结果一致,OLA1在DF和SF中的表达趋势与深度测序结果正好相反,但差异不显著。本研究筛选出的4个表达下调基因可能是牛卵泡发育过程中抑制卵泡发育的候选基因。 相似文献
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Nitric oxide (NO) is an endogenous gas that serves as a biologic messenger in many physiologic processes including neurotransmission, blood-pressure control, the immune system's ability to kill tumor cells, and wound healing. NO is produced after oxidation of L-arginine by a family of nitric oxide synthase (NOS) enzymes. Two of the NOS enzymes are present continuously and are thereby termed constitutive NOS. One of the enzymes, inducible NOS, is not typically expressed in resting cells and is induced by various substances including endotoxin, some cytokines, and microbial products. Thus, NO often has paradoxical activities. When NO is over- or underproduced, it can result in potentiation of disease states with disastrous results. This review discusses the biochemistry of NO, its functions in normal and disease states, and therapy for modulating NO production in disease states. 相似文献
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Endo D Yamamoto Y Yamaguchi-Yamada M Nakamuta N Taniguchi K 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2011,73(4):423-430
Nitric oxide (NO) is a free radical and produced from L-arginine by nitric oxide synthase (NOS). Since NO is recently suggested to be involved in olfactory perception, the expression of eNOS, an isoform of NOS, was examined in the rat olfactory epithelium. The activity of NADPH-diaphorase was also examined as a marker of NOS. In the dorsomedial region of the nasal cavity, intensely positive reactions for NADPH-diaphorase were observed in the entire cytoplasm of sensory cells (olfactory cells). By immunohistochemistry, intensely positive reactions for eNOS were also found in the dorsomedial region of the nasal cavity. These reactions were observed on the free border of the olfactory epithelium. By immunoelectron microscopy, positive reactions for eNOS were found in the cilia of olfactory cells. In addition, in situ hybridization analysis of the olfactory epithelium revealed the expression of eNOS mRNA in the olfactory cells. These results indicate the presence of eNOS in the olfactory cells of the rat, and differential expression of eNOS in the olfactory epithelium depending on the regions of the nasal cavity. In addition, NO produced by eNOS may be involved in olfactory perception in the cilia of olfactory cells. 相似文献
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The expression of inflammatory mediators was examined in pigs experimentally infected with Actinobacillus pleuropneumoniae. The activity of nitric oxide synthase 2 (NOS2) and cyclooxygenase-2 (COX-2) was determined by measuring nitric oxide (NO) and prostaglandin E2 (PGE2) in bronchoalveolar lavage fluid in response to A. pleuropneumoniae in vivo. By in situ hybridization and immunohistochemistry, both NOS2 and COX-2 enzymes were detected in neutrophils and macrophages that had infiltrated into alveolar spaces. The sharp increase in PGE2 concentration preceded the increase in the concentrations of NO. NO levels were highly correlated with PGE2 level (rs=0.7218, P <0.05). The NO levels were positively correlated with lung lesion scores (rs=0.9087, P <0.05) until 24 hours postinoculation (hpi) as were the lung lesion scores and PGE2 levels (rs=0.925, P <0.01). High levels of PGE2 produced by COX-2 are generated in early infection (6 hpi). However, in later stages of infection (12-36 hpi), there is participation of NO and PGE2 accompanied by coinduction of both NOS2 and COX-2. 相似文献
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Koh PO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2008,70(7):747-750
Nitric oxide (NO) is produced by three NO synthases (NOS), iNOS, eNOS, and nNOS. Production of NO by iNOS plays key roles in neurodegeneration, while eNOS is a protective enzyme. This study investigated the neuroprotective effect of melatonin and the levels of NOS isoforms induced by melatonin in ischemic brain injury. Adult male rats were treated with melatonin (5 mg/kg) or vehicle prior to middle cerebral artery occlusion (MCAO). Brain samples were collected at 24 hr after the onset of occlusion. Results confirmed that melatonin significantly reduces infarct area. Western blot analysis was used to evaluate the expression levels of iNOS, eNOS, and nNOS. The level of iNOS and nNOS increased in vehicle-treated animals, while melatonin prevented injury-induced increase of iNOS. In contrast to iNOS levels, eNOS levels decreased in vehicle-treated animals, while melatonin prevented the injury-induced decrease of eNOS. This study provides further evidence that melatonin exerts neuroprotective effects, and the regulation of NOS isoforms by melatonin may contribute to the neuroprotective effects. 相似文献
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Louis E Remer KA Doherr MG Neumann U Jungi T Schawalder P Spreng D 《Veterinary journal (London, England : 1997)》2006,172(3):466-472
Osteoarthritis due to cranial cruciate ligament (CCL) rupture or hip dysplasia is one of the most important causes of chronic lameness in dogs. This study aimed at comparing nitric oxide (NO) production by the CCL with that of the femoral head ligament (FHL) and the medial collateral ligament (MCL), and investigating the pathway of NO production and the concomitant metalloproteinase (MMP) activity in the presence or absence of an inflammatory stimulus. Ligaments of normal dogs were subjected to different stimuli, and NO and MMP activity from explant culture supernatants were compared. The results showed that in explant cultures of the canine CCL more NO was produced than in those of the other two ligaments. A higher level of NO was produced when CCLs were exposed to the inducible nitric oxide synthase (iNOS)-inducing cocktail TNF/IL-1/LPS, and NO synthesis could be inhibited by both l-NMMA, a general nitric oxide synthase (NOS) inhibitor and l-NIL, a specific iNOS inhibitor. However, a correlation between NO synthesis and iNOS expression levels as determined by immunohistochemistry was not observed. In contrast to CCL, no evidence for iNOS-dependent NO synthesis was observed for MCL and FHL. The CCL produced less MMP than MCL and FHL, and no correlation between MMP and NO could be demonstrated. MMP activity in the CCL increased significantly after 48 h of incubation with the inflammatory stimulus. The results suggest that in canine osteoarthritis NO synthesized by canine CCL plays a more important role in the pathogenesis of osteoarthritis of the stifle than that synthesized by FHL and MCL. 相似文献
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Bull spermatozoa were examined for the presence and localization of constitutive Nitric Oxide Synthase (NOS), as nitric oxide (NO) is involved in calcium-dependent capacitation. In bull spermatozoa, NO generation is enhanced by l-arginine (3 microm) and abolished by the NOS-inhibitor N-nitro-l-arginine methyl ester (l-NAME). In addition, presence of NOS in bull spermatozoa was verified by immunohistochemistry, revealing the existence of both neuronal NOS (nNOS) and endothelial NOS (eNOS) immunoreaction. These findings were confirmed by Western blot technique, showing immunoreactive bands at 161 kDa (nNOS) and 133 kDa (eNOS). Confocal laser microscopy localized nNOS related immunofluorescence at the acrosome cap of sperms and their flagellum-mainpart. This technique also identified eNOS staining spread over the spermatozoan head. In conclusion, immunohistochemistry, Western blot technique, and NO generation suggest the presence of n- and eNOS in bull spermatozoa. 相似文献
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Hunter RP 《Animal health research reviews / Conference of Research Workers in Animal Diseases》2002,3(2):119-133
Inflammation is a process consisting of a complex of cytological and chemical reactions which occur in and around affected blood vessels and adjacent tissues in response to an injury caused by a physical, chemical or biological insult. Much work has been performed in the past several years investigating inducible nitric oxide synthase (NOS, EC 1.14.13.39) and nitric oxide in inflammation. This has resulted in a rapid increase in knowledge about iNOS and nitric oxide. Nitric oxide formation from inducible NOS is regulated by numerous inflammatory mediators, often with contradictory effects, depending upon the type and duration of the inflammatory insult. Equine medicine appears to have benefited the most from the increased interest in this small, inflammatory mediator. Most of the information on nitric oxide in traditional veterinary species has been produced using models or naturally occurring inflammatory diseases of this species. 相似文献
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Tan X Sun WD Li JC Pan JQ Liu YJ Wang JY Wang XL 《Veterinary journal (London, England : 1997)》2007,173(1):151-157
This study investigated nitric oxide synthase (NOS) expression in the endothelium of pulmonary arterioles of broilers during the development of pulmonary hypertension syndrome (PHS). PHS was triggered by exposing broilers to sub-thermoneutral (cool) temperatures and an additional 1.0% L-arginine was added to the basal diet to evaluate the effects of supplemental L-arginine on nitric oxide (NO) production, endothelial NOS expression, and the incidence of PHS. Cumulative mortality from PHS, right/total ventricle weight ratios (RV/TV), and body weights were recorded. Plasma NO concentration and NOS expression in the endothelium of pulmonary arterioles with an outer diameter ranging from 100 to 200 microm were determined. Birds exposed to cool temperatures had increased pulmonary hypertension and PHS mortality and diminished endothelial NOS expression. Supplemental dietary L-arginine reduced PHS mortality and elicited higher NOS expression within the pulmonary endothelium coincident with elevated NO production. The results demonstrated that broilers developing PHS exhibited diminished NOS expression in the endothelium of their pulmonary arterioles. Supplemental L-arginine prevented the reduced expression of NOS in the pulmonary endothelium, which might contribute to the increased production of NO by the pulmonary vasculature. 相似文献