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1.
In teleosts, as in other vertebrates, the secretion of pituitary gonadotropin (GTH) is mediated by the hypothalamic decapeptide, gonadotropin-releasing hormone (GnRH). Recent findings in teleosts indicate that GnRH receptors are not restricted to the pituitary gonadotropes and are also associated with somatotropes as well as being present in a number of other tissues. In the present study, we provide novel information on GnRH binding in a number of extrapituitary tissues in goldfish. However, we do not intend to provide full characterization of GnRH binding sites in various extrapituitary tissues in goldfish as this would clearly be outside the scope of this paper. In this study we examined GnRH binding in a number of extrapituitary tissues in goldfish and observed specific binding in ovary, testis, brain, liver and kidney. No specific GnRH binding was observed in muscle, skin, gut, gill and heart. In general, the present findings together with the results of other studies carried out in our laboratory demonstrate that mature goldfish ovary and testis contain two classes of GnRH binding sites, high affinity/low capacity and low affinity/high capacity sites with binding characteristics similar to those of the pituitary GnRH receptors. The brain of goldfish was also found to contain two classes of GnRH binding sites, a super-high affinity/low capacity and a low affinity/high capacity sites. Furthermore, study of goldfish liver and kidney demonstrated the presence of a single class of GnRH binding sites with characteristics different from those of pituitary, ovary, testis and brain. Overall, it is evident that goldfish contains a family of GnRH binding sites which can be classified into four groups based on binding affinities: 1) A class of high affinity binding sites present in the pituitary, ovary and testis, 2) a class of super high affinity sites so far only detected in the brain, 3) a class of intermediate-affinity GnRH binding sites in the liver and kidney, and 4) a class of low affinity binding sites present in all the tissues containing specific GnRH binding sites except for liver and kidney. 相似文献
2.
Germinal vesicle migration (GVM) and/or dissolution (GVD) were measured in goldfish oocytes, treated with 17α, 20β dihydroxyprogesterone (DHP) and other compounds considered to effect the cytoskeleton and oxidative phosphorylation,in vitro. Administration of DHP reinitiated meiotic maturation, increasing GVM and GVD in goldfish oocytes. Addition of 2,4-dinitrophenol
(DNP) to the incubation medium significantly inhibited DHP-induced GVM and GVD. The DNP effect was found to be partially reversible
after 24 h and could be reversed fully after a further delay of approximately 24h. Treatment of goldfish oocytes with demecolcine
(DE; a colchicine derivative also known as colcemid) induces GVM to the micropyle without effecting GVD; while Cytochalasin-B
which inhibits microfilament polymerization impairs both GVM and GVD. Administration of DNP, significantly inhibited DE-induced
GVM, suggesting that GVM as well as GVD are dependent upon the process of oxidative phosphorylation. Addition of adenosine-5′
-triphosphate (ATP) at low concentrations (0.01–0.1 mM) did not effect DHP-induced or DNP-inhibited GVD in goldfish oocytes.
The present results are consistent with the idea that migration of the oocyte nucleus during meiosis reinitiation has an energy
requirement and involves participation by the cytoskeleton. 相似文献
3.
Na Na Kim Jehee Lee Hamid R. Habibi Cheol Young Choi 《Fish physiology and biochemistry》2013,39(3):417-429
The caspase-3 appears to be a key protease in the apoptotic pathway. We identified caspase-3 complementary DNAs from the ovaries of the protandrous cinnamon clownfish (Amphiprion melanopus), and investigated its mRNA and proteins, and activity levels during the sex change (I, mature male; II, male at 90 days after removing of the female; and III, mature female). The nucleotide sequence of the caspase-3 cDNA was 969 base pairs in length with open reading frames encoding peptides of 282 amino acids. The caspase-3 mRNA and protein, and activity levels in stages of the mature gonad are higher than those of the development gonad stage. To understand the effect of gonadotropin-releasing hormone (GnRH) on gonad apoptosis, we examined expression of genes caspase-3 mRNA and activity level in immature cinnamon clownfish gonads after GnRH analogue (GnRHa). The findings support the hypothesis that caspase-3 expression is associated with both testicular and ovarian development, and suggests that it may play a role in the control of ovarian development in cinnamon clownfish. Also, we demonstrate that GnRH agonists stimulate caspase-3 production which can in turn stimulate apoptosis. The present study provides a framework for better understanding of the role of caspase-3 during sex change processes in fish. 相似文献
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5.
Bibalani GH Bazhrang Z Mohsenifar H Shibaei N Joodi L 《Pakistan journal of biological sciences: PJBS》2008,11(8):1126-1131
A pulling effect by side roots is one way in which roots help to side in-plane strong of a little depth soil mass. In contrast to the effect of vertically-enlarge roots, whereby soil is strengthened by an increase in its shear strength, the pulling effect strengthens the soil by increasing the tensile strength of the rooted soil zone. To verify whether or not a pulling effect exists in the root system of Prunus avium in the Roudsar, North Iran and to study the importance and size of this effect, a direct in situ test was led at a site in the Chaboksar Forests. The results from the site showed that, in the surface soil (0-30 cm), Side roots can provide a pull force of up to 490-712 N (Newtons) over a vertical cross-section area of 20-50 cm2, or an enhance in the pulling stability of the rooted soil by about 48.1%. The test results suggest that, together with the Prunus avium vertical roots, which keep the little depth rooted soil zone to the deep and more stable soil mass, the side roots of the Prunus avium, with their pulling effect, are able to make less against little depth instability in the forest slopes, such as little depth slide, to a certain degree. 相似文献
6.
Adnan Abbasi Amin Oujifard Mansour Torfi Mozanzadeh Hassan Habibi Mahmoud Nafisi Bahabadi 《Aquaculture Nutrition》2020,26(4):1131-1142
A 56‐day nutritional research was performed to examine the influence of alternative vegetal protein and lipid sources on performance of yellowfin seabream fry (Acanthopagrus latus) (0.5 ± 0.0 g). In this regard, five isoproteic (Ca. 500 g/kg) and isolipidic (Ca. 150 g/kg) diets were formulated in which fish meal (FM) and fish oil (FO) were simultaneously replaced with blends of plant proteins (PP, soybean meal and corn gluten) and vegetal oils (VO, canola and soybean oils) at 20% (SR20), 40% (SR40), 60% (SR40) and 80% (SR80) levels, respectively; meanwhile, a control diet (SR0) was formulated based on FM and FO. Growth and feed utilization were not influenced by experimental diets. The fatty acid profile of fillet drastically altered by dietary treatments. Fish fed with the SR60 and SR80 feeds had higher total protease, trypsin and α‐amylase activities than other treatments. The antioxidant enzyme activities and glutathione content in liver were enhanced in fish fed with the SR40, SR60 and SR80 diets. Skin mucosal immune parameters including total protein content, alkaline phosphatase and alternative complement pathway activities in the control group were relatively lower than the vegetal treatments. According to these results, it is recommended that 410 g/kg of FM and 45 g of FO/kg can be replaced with alternative vegetal sources in diet for A. latus fry. 相似文献
7.
Asghar Ramezanian Rahil Dadgar Fariborz Habibi 《International Journal of Fruit Science》2018,18(1):68-84
ABSTRACTTo evaluate the effects of preharvest foliar application of calcium chloride (CaCl2), potassium chloride (KCl), and salicylic acid (SA) on postharvest quantitative and qualitative attributes and storage life of “Washington navel” orange, an experiment was conducted during two consecutive years. Solutions including CaCl2 (1.5% and 3%), KCl (1.5% and 3%), SA (0.015%, 0.03% and 0.045%), and the combination of CaCl2, KCl, and SA were sprayed on the canopy at the end of the first stage of fruit growth one month after full bloom (fruit diameter was 20 mm) and repeated in late September. The fruits were harvested at commercial maturity stage and were stored at 5°C with 85 ± 5% relative humidity (RH) for 90 days. Quantitative and qualitative characteristics were assessed every month. Preharvest KCl treatment had no significant effect on measured parameters. However, CaCl2 and SA treatments had the most impact on the quantitative and qualitative characteristics, such as firmness and phenolic content of fruit during storage. The SA treatment enhanced fruit appearance and nutritional value compared to the control but could not prevent the weight loss during storage. The results showed that preharvest spray of CaCl2, KCl, SA, and their combination had positive effects on storability of “Washington navel” orange fruit during storage. However, the effect of Ca and SA was more. Application of Ca, K, and SA could be beneficial for orange postharvest instead of mixed elements fertilizers. 相似文献
8.
KRS Morgan HR Milner A Tikekar HL Smith AR Coomer 《New Zealand veterinary journal》2018,66(4):205-209
AIMS: To report on the long-term outcomes of hydraulic artificial urethral sphincter (HAUS) placement for the correction of urethral sphincter mechanism incompetence (USMI) in New Zealand dogs.
METHODS: Retrospective data were obtained from cases of dogs which had a HAUS placed after failed medical and/or surgical management of USMI between August 2012 and November 2016. Owner assessment of urinary incontinence was evaluated by an online survey in May 2017 using a visual analogue scale (0 being normal, 100 being severely affected) for the frequency, volume and severity of any straining to urinate, immediately prior to the placement of the HAUS and at the time of the survey. The number of days between surgery and the completion of survey were recorded.
RESULTS: Seven females and two male dogs, which were all desexed except for one female, were eligible for inclusion in the study. The period of follow-up following HAUS placement ranged from 206–1,685 days. Following HAUS placement, frequency and volume of urinary incontinence decreased for six dogs and were practically unchanged for three dogs. The median frequency score decreased from 70 to 13 and the volume score decreased from 73 to 12. There was no consistent change in the perceived degree of straining to urinate. Complications occurred in three dogs; one required repositioning of a dislodged injection port, one required management for haematuria and a hypoplastic bladder, and one required surgical removal of fibrous tissue around the HAUS cuff.
CONCLUSIONS AND CLINICAL RELEVENCE: HAUS placement was an effective method for the treatment of persistent USMI in most dogs and provided good clinical results based on owner assessment. The technique was associated with few complications and allowed successful long-term control of urinary incontinence without the need for medical management. 相似文献
9.
"人、机、料、法、环"与兽药GMP的关系 总被引：1，自引：0，他引：1
本文尝试将质量管理学中五要素"人、机、料、法、环"的重要概念引入到兽药GMP管理体系中来,便于记忆和理解,有助于进一步认识、掌握和运行GMP. 相似文献
10.
当前兽药地方标准清理工作已进入攻关阶段,但在清理地方标准的实际工作中尚存在一些问题,笔者分析了这些具体问题,认为在升标工作中,政府应当给予合理的政策扶持,加快地方标准清理工作进度,保护企业利益;企业应当着重做好品种筛选,合理安排临床试验资金投入;企业通过采取联合参与升标方式,减少资金投入;对于移植外省标准,可采取不同措施妥善解决;为保证升标工作顺利进行,农业部和各省兽医行政管理部门应做好升标培训指导工作. 相似文献