三种脑-肠肽对人绒毛膜促性腺激素分泌的影响

本工作利用灌流技术观察了3种脑-肠肽(P物质,CCK及NT)对新鲜人工流产的绒毛hCG分泌的影响。结果表明,P物质,CCK及NT均明显刺激绒毛释放hCG,并发现CCK作用大于P物质及NT。提示,hCG的分泌可能受这3种脑-肠肽的调节。     

感染NDV后鸡腺胃中P物质和VIP的分布及动态观察

70只35日龄SPF鸡随机分成对照组和攻毒组.攻毒组经腹腔接种鸡新城疫病毒后,分别取腺胃,并用免疫组织化学方法检测组织中NDV、P物质和VIP的分布及动态变化.结果表明：P物质和VIP在两组鸡的腺胃中都有存在,且三种物质的表达量呈现正相关性,其含量在感染后有增加,证明了P物质和VIP在感染NDV后有调节动物防御系统的作用.     

鸡胚对小鼠抗衰老和抗疲劳的作用

以小白鼠为研究对象 ,分别进行了鸡胚在小鼠抗衰老和抗疲劳方面作用的实验 .实验结果证明 ,用 10d龄鸡胚物质灌服小鼠 4 2d后 ,小鼠血浆SOD含量明显升高 ,浆MDA水平显著降低 (P <0 .0 1) ,从而证明鸡胚对小鼠有显著的抗衰老作用 .游泳实验证明 ,用 10d龄鸡胚物质给小鼠灌服 10d后 ,游泳持续时间较对照组显著提高 (P <0 .0 1) .     

喜德阉鸡与市售几种鸡肉的品质比较研究

以白羽肉鸡、麻黄鸡、三黄鸡、青脚麻鸡和喜德阉鸡为研究对象,探究喜德阉鸡与市场常见的几种鸡肉品质的差异.对5种鸡胸肉进行了物理、营养特性、氨基酸含量以及风味物质检测.结果表明,喜德阉鸡在p H值、水分含量和肉色亮度值(L*值)上显著高于麻黄鸡、三黄鸡和青脚麻鸡,而蒸煮损失率与剪切力显著低于其他鸡肉(P <0.05).喜德阉鸡在粗蛋白含量上显著高于白羽肉鸡、三黄鸡和青脚麻鸡,而其粗脂肪含量则显著低于麻黄鸡和青脚麻鸡(P <0. 05).喜德阉鸡鸡胸肉中检出总氨基酸、鲜味氨基酸与必需氨基酸含量最高(P <0. 05),且精氨酸、异亮氨酸、蛋氨酸及苏氨酸4种必需氨基酸含量均最高(P <0. 05). 5种肉鸡中共检测出28种挥发性物质,主要包括醇类、醛类、烷烃类、酸类和芳香烃类物质,喜德阉鸡中的醇类物质(13. 94%)、醛类物质(62. 73%)和烷烃类物质(8.12%)均为最高,其中正己醛(58. 72%)、1-辛烯-3-醇(10. 39%)是其富含油脂香味的重要来源.因此,喜德阉鸡较白羽肉鸡、麻黄鸡、三黄鸡和青脚麻鸡有更为优质的肉质以及独特的风味特性.     

甘肃嘉峪关戏台建筑彩画胶结材料的氨基酸分析

为了鉴定嘉峪关戏台建筑彩画使用的胶料,使用氨基酸分析法测定了古代常用胶料鸡蛋、动物胶及奶类三种物质的氨基酸组成比.分析了嘉峪关戏台建筑彩画样品,通过将样品和标样的氨基酸组成比进行主成分分析,确定了样品胶料的种类.得出了嘉峪关戏台建筑彩画是采用动物胶作为彩画胶结材料的结论.     

硒氟联用对小鼠脑内PSD厚度及SOD活性的影响

采用饮水加氟、加硒的方法,用电镜和计算机图像分析仪分析研究了小鼠学习记忆相关脑区——海马CA\-3区GrayI型突触后致密物质(PSD)厚度的变化,并用生化方法测定了其脑内SOD活性的变化.结果表明高氟能引起小鼠脑内海马CA\-3区突触后致密物质厚度极显著变小(P＜0.01或P＜0.001)的病理性变化,并能降低其脑内SOD活性;适当量的硒可拮抗氟的这种作用,但硒量过高或过低则与氟产生协同毒性作用.提示一定量的硒对氟致小鼠脑内突触结构损伤有改善作用,并且这种改善作用可能和硒提高其脑内\{SOD\}活性有关.     

鸡胚蛋白提取工艺优化及其抗氧化活性研究

文章以孵化14d的鸡胚为原料,采用缓冲液法对鸡胚中的蛋白质进行提取研究,评价了其体外抗氧化活性并分析了其氨基酸组成。采用乙醚低温回流脱去鸡胚干粉中脂肪,通过差示扫描量热仪(differential scanning calorimetry,DSC)确定粗蛋白的变性起始温度为62.47℃。在单因素的基础上,应用Box-Behnken中心组合实验设计建立数学模型,得到了最优提取条件为料液比1∶16、温度50℃、时间116min,此条件下鸡胚蛋白提取率为73.87%。按此方法提取的鸡胚蛋白对1,1二苯基-2-三硝基苯肼自由基(DPPH·)、羟基自由基(·OH)具有较强的清除能力。鸡胚蛋白中必需氨基酸组成齐全,含量高,是一种理想的动物蛋白资源,有待进一步开发。     

猪红血球珠蛋白水解液培养动物细胞

本文报道了从猪血中制备珠蛋白水解液的流程,测定了其总氮量并初步分析了其氨基酸组成。同时用珠蛋白水解液培养了几种动物原代细胞,并在培养的鸡胚成纤维细胞上感染鸡新城疫工系病毒。经试验,初步证明猪血的水解珠蛋白营养液对培养各种动物原代细胞和适应病毒可以正常生长和繁殖。     

宇宙中也有氨基酸

美国射电天文学家在银河系中心附近稠密的星际气体云和尘埃云中发现了一种重要的蛋白质分子物质——由最简单氨基酸组成的甘氨酸。该研究小组负责人,伊利诺伊州大学科学家刘易斯·斯奈焦尔在美国天文学协会年会上通报了这一发现。宇宙     

α-Synuclein蛋白过表达对小鼠纹状体的影响

 帕金森病是世界第二大老年神经退行性疾病,致病机理极为复杂。α-synuclein（α-syn）是帕金森病主要病理特征的路易小体的主要组成成分,其突变基因α-syn A30P 也与部分家族性帕金森相关。通过对过表达野生型人源α-syn WT 及其突变体α-syn A30P 蛋白的转基因小鼠的行为学检验、脑部纹状体中氧化应激水平以及儿茶酚胺异喹啉物质水平的检测,研究过表达α-syn 蛋白对小鼠纹状体产生的影响。结果显示转基因小鼠模型与正常鼠相比,其协调能力明显下降,纹状体与全脑的比例显著降低。同时,模型鼠脑中的氧化应激水平与儿茶酚胺异喹啉物质的表达水平均显著升高。研究结果说明,α-syn 蛋白及其突变体的过表达会引起小鼠脑部纹状体中氧化应激水平与儿茶酚异喹啉物质表达水平的升高,从而导致纹状体组织严重损伤。     

Stimulation of connective tissue cell growth by substance P and substance K

Connective tissue cells proliferate actively when cultured in the presence of serum. Platelet-derived growth factor (PDGF), a basic protein of relative molecular mass approximately 30,000, has been identified as the major serum mitogen for these cells; its main physiological/pathophysiological role may be to initiate wound healing in connection with tissue injury. However, growth of cultured cells is also influenced by several other factors, including epidermal growth factor, fibroblast growth factor, insulin and somatomedins. Furthermore, Rozengurt and Sinnett-Smith recently showed that bombesin, a neuroendocrine peptide isolated from frog skin, stimulates DNA synthesis and cell division in cultures of a specific subtype of 3T3 cells. Substance P and substance K (also known as neurokinin A or neuromedin L) are mammalian peptides belonging to the tachykinin family. Substance P has been studied extensively; it is distributed widely throughout the central and peripheral nervous system, including primary sensory neurones, and can be released in the periphery from axon collaterals of stimulated pain fibres and contribute to the inflammatory response. Substance K is a member of the tachykinin family isolated from mammalian spinal cord; Nawa et al. determined the primary structure of two types of substance P precursors, one of which contained a sequence homologous to substance K, as well as the sequence of substance P. We report here that substance P and substance K stimulate DNA synthesis in cultured arterial smooth muscle cells and human skin fibroblasts, and that this stimulation is inhibited by the substance P-antagonist spantide.     

Cycloheximide-sensitive synthesis of substance P by isolated dorsal root ganglia

Substance P (Arg-Pro-Lys-Pro-Gln-Gln-Phe-Phe-Gly-Leu-Met-NH2) may be used as a neurotransmitter by certain primary afferent neurones, particularly those carrying pain impulses. Substance P-like immunoreactivity has been localised to the cell bodies of one population of dorsal root ganglion neurones by immunocytochemistry. It is contained in vesicles in the central terminals of these neurones, and has also been demonstrated in the peripheral terminals. As axons and terminals have very little capacity for peptide biosynthesis, it is possible that substance P is synthesised and packaged in the perikaryon and transported to the terminals by an axoplasmic transport process. Consistent with this is the finding that substance P accumulates proximal to a ligature placed on the dorsal root. There has, however, been no direct demonstration of the biosynthesis of substance P in the nervous system. We report here that rat dorsal root ganglia incorporate 35S-methionine into substance P, characterised as authentic by immunoprecipitation followed by HPLC. There is a delay of 1-2 h between addition of label and its incorporation into substance P. Synthesis is blocked by cycloheximde suggesting that, in dorsal root ganglia, substance P is synthesised by a conventional ribosomal process. Synthesis of substance P is reduced by some 90% in ganglia from rats treated neonatally with capsaicin, a drug which is thought to destroy a population of primary afferent neurones.     

P物质在正常与致聋白腰文鸟前脑X区表达水平的差异研究

通过免疫组织化学方法对正常和致聋不同时程的成年雄性白腰文鸟X区P物质的表达进行了定量分析,结果发现:致聋后鸟的X区P物质表达量显著减少.X区是鸣禽鸣唱学习的重要核团,P物质也是一种重要的神经调质,提示X区P物质可能参与了鸣禽鸣唱可塑性的调节或鸣唱模式的维持.     

Sensory transmitters regulate intracellular calcium in dorsal horn neurons

Primary afferent terminals in the dorsal horn of the spinal cord release excitatory amino acid and peptide transmitters that initiate the central processing of nociceptive information. The postsynaptic actions of amino acid transmitters on spinal neurons have been well characterized, but the cellular basis of peptide actions remains unclear. Substance P is the best characterized of the peptides present in sensory neurons and has been shown to depolarize dorsal horn neurons and to facilitate nociceptive reflexes. To determine the mechanisms by which substance P contributes to afferent synaptic transmission, we have monitored the levels of intracellular calcium in single isolated rat dorsal horn neurons and report that substance P can produce a prolonged elevation in calcium concentration by mobilizing its release from intracellular stores. This elevation may contribute to the long-term changes in the excitable properties of dorsal horn neurons that occur following afferent fibre stimulation. We have also found that L-glutamate elevates intracellular calcium in substance P-sensitive dorsal horn neurons by increasing calcium influx. These results provide a direct demonstration of intracellular calcium changes in response to neuropeptides in mammalian central neurons. They also indicate that there is convergent regulation of intracellular calcium in dorsal horn neurons by two different classes of sensory transmitters that are co-released from the same afferent terminals.     

兔圆小囊淋巴组织中11种脑肠肽类物质免疫组织化学定位观察

采用免疫组化方法,观察P物质、胰高血糖素、胃泌素、胰多肽、生长抑素、促甲状腺素、促肾上腺素皮质激素、降钙素、胰岛素、突触素、血管活性肠肽等11种脑肠肽类物质在兔圆小囊淋巴组织中的分布及定位。研究发现上述物质在兔圆小囊淋巴组织及粘膜内均有分布,但在淋巴组织中上述物质阳性细胞的数量及分布部位各不相同。其中降钙素、胰岛素2种物质,在粘膜下淋巴组织中分布很少,只可偶见阳性细胞;突触素阳性细胞稍多于上述2种物质;P物质、胃泌素、生长抑素、血管活性肠肽阳性细胞较多,尤其是在圆顶上部淋巴组织和淋巴滤泡中均大量散在分布;促肾上腺素、生长激素、促甲状腺素阳性细胞也比较多,主要分布在淋巴滤泡部位,圆顶上部淋巴组织虽然也存在阳性细胞,但数量明显少于淋巴滤泡部位;胰多肽主要分布在圆顶上部的淋巴组织中,淋巴滤泡处较少。     

滇中地区路旁紫茎泽兰在不同光水平下的分布格局

 在紫茎泽兰的入侵地滇中地区,于4条公路（其中高级公路与低级公路各2条）旁共选择13个不同光水平下的样地,研究了公路旁紫茎泽兰在3种光水平下分布格局的差异.结果表明3种光水平极显著影响路旁紫茎泽兰的分布（p<0.001）;高光水平比中、低光水平更促进路旁紫茎泽兰的入侵与向远距离扩散;同样在低光水平下,高等级公路比低级公路更促进紫茎泽兰的入侵与扩散.     

P物质在非中枢神经系统中的作用

P物质是广泛分布于细神经纤维内的一种神经肽，在非中枢神经系统中的作用十分广泛，可在各种系统如心血管系统、呼吸道、胃肠道、泌尿生殖道及骨组织中发挥作用，许多疾病如哮喘、慢支、膀胱炎、肠炎、偏头疼、呕吐、抑郁及疼痛发作等均与P物质有关。本文就P物质在非中枢神经系统中的生理、病理生理作用进行综述。     

初孵扬子鳄脑垂体P物质的免疫组织化学研究

用免疫组织化学方法观察了P物质在初孵扬子鳄脑垂体的分布特点.P物质阳性细胞分布于初孵扬子鳄脑垂体内侧腺垂体部,阳性纤维分布于初孵扬子鳄脑垂体外侧的神经部.结果表明P物质可能对垂体内分泌细胞有调节作用.     

Substance P raises neuronal membrane excitability by reducing inward rectification

Much interest has recently centred on the properties of peptides that modulate the excitability of nerve cells. Such compounds include the undecapeptide substance P, which is particularly well established as an excitatory neurotransmitter, and we examine here its effects on magnocellular cholinergic neurones taken from the medial and ventral aspects of the globus pallidus of newborn rats and grown in dissociated culture. These neurones have previously been shown to respond to substance P3 and are analogous to the nucleus basalis of Meynert in man, which gives a diffuse projection to the cerebral cortex and whose degeneration is the likely cause of Alzheimer's disease. Substance P depolarizes these cultured neurones by reducing an inwardly rectifying potassium conductances; this conductance has been found in several neuronal types and has similar properties to those of certain other cells. As discussed below, modulation of inward (or anomalous) rectification by substance P implies a self-reinforcing element to the depolarization caused by the peptide.     

P物质对大鼠星状神经节细胞的影响

应用细胞内生物电记录方法，观察神经肽Ｐ物质（ＳＰ）对大鼠星状神经节能细胞的影响，用灌流或用加压向细胞周围施加ＳＰ可使部分细胞发生膜除极反应，用低钙或用含河豚毒素克氏液灌流神经节，并不影响ＳＰ引起的除极反应的幅度和时程。ＳＰ引起除极反应的同时常伴有膜电阻增大，当膜电位增大时，除极化反应幅度变小，反转电位为－８０ｍＶ至－１００ｍＶ，研究表明，ＳＰ对部分星状神经节细胞具有直接兴奋作用，并且ＳＰ对细胞膜的