西藏湍流蛙类一新种

在西藏墨脱采集到1种与Odorrana graminea、O.chloronota和O.livida体背绿色和指端膨大具沟的湍流蛙类相近的物种,经鉴定为新种,命名为墨脱臭蛙Odorrana zhaoi。新种具有以下主要特征:上唇缘具有金黄色条纹;鼓膜圆形,显著,TD:ED为0.56 ;背侧褶弱,背部皮肤除后部有小疣粒外光滑,体侧有疣粒和小刺; 4肢背面有横斑纹;无外突;雄性具1对外声囊和咽胸部椭圆形小刺团,无肱腺。     

A small trypsin inhibitor from the frog of Odorrana grahami

A novel peptide inhibitor (OGTI) of serine protease with a molecular weight of 1949.8, was purified from the skin secretion of the frog, Odorrana grahami. Of the tested serine proteases, OGTI only inhibited the hydrolysis activity of trypsin on synthetic chromogenic substrate. This precursor deduced from the cDNA sequence is composed of 70 amino acid residues. The mature OGTI contains 17 amino acid residues including a six-residue loop disulfided by two half-cysteines (AVNIPFKVHFRCKAAFC). In addition to its unique six-residue loop, the overall structure and precursor of OGTI are different from those of other serine protease inhibitors. It is also one of the smallest serine protease inhibitors ever found.     

陕西省发现绿臭蛙

在陕西省宁强县青木川国家级自然保护区采集了6只臭蛙类标本,经形态特征比较,鉴定为绿臭蛙(Odorrana margaretae),为陕西省首次发现。本文对其特征和分布进行了讨论。     

Gene cloning and characterization of novel antinociceptive peptide from the brain of the frog, Odorrana grahami

Amphibian opiate peptides including dermorphins and deltorpins have been recently found only in the skin of South American frogs belonging to the subfamily Phyllomedusinae (Phyllomedusa, Agalychnis and Pachymedusa species). No opiate peptides have ever been identified from other amphibians or organs except skin. Here we report the purification and characterization of a novel antinociceptive peptide named odorranaopin from the homogenates of the frog brains, Odorrana grahami, which is also the first antinociceptive peptide found in Ranidae amphibian. Odorranaopin comprises 17 amino acid residues with the sequence of DYTIRTRLHQESSRKVL (Mr 2102 Da). The cDNA encoding odorranaopin was cloned from the frog brain cDNA library, and it was confirmed to be a specific gene. The odorranaopin precursor deduced is composed of 61 amino acid residues including the predicted signal peptide, acidic spacer peptide and mature odorranaopin positioned at the C-terminus. Odorranaopin could inhibit nociceptive responses induced by formalin and acetic acid. It also inhibited the contractile responses of ileum smooth muscle induced by bradykinin, implying that the antinociceptive activity of odorranaopin possibly results from its blockade on bradykinin or bradykinin receptor functions. Odorranaopin is the first antinociceptive peptide found in Ranidae amphibian.     

光雾臭蛙的分布新纪录及地理变异

2009年8月在湖北省保康县五道峡自然保护区采到1种臭蛙类标本,与湖北省已有记录的绿臭蛙Odorrana margaretae明显不同,经与四川南江光雾山标本进行形态特征比较和DNA序列比对,鉴定为光雾臭蛙O.kuangwuensis。湖北省保康县光雾臭蛙体长大于模式产地标本;指序3、4、2、1,第2指与第1指几等长;关节下瘤显著,第2～4指具指基下瘤;4肢背面绿色与黑酱色横纹相间排列,横纹间无云状斑,股、胫部横纹3～4条,跗部和前臂2～3条。湖北省保康县五道峡与四川省南江县光雾山相距近5个经度,是否因地理隔离造成种群间的差异,有待进一步研究。     

凹耳臭蛙消化系统解剖学及组织学观察

对凹耳臭蛙Odorrana tormota消化系统进行了解剖学及组织学观察。消化道可以分为口腔、咽、食道、胃、十二指肠、回肠和直肠,末端开口于泄殖腔。肝脏和胰腺为消化腺。消化道管壁的组织结构均为4层结构,由管腔向外依次为黏膜层、黏膜下层、肌层和浆膜。胃黏膜层中含有许多胃腺,可明显分为腺颈部和腺体部。小肠含有十二指肠腺,直肠含有直肠腺。肝脏发达,分为左、中、右3叶,肝小叶界限不明显。胰腺中的腺泡由腺细胞围成。凹耳臭蛙肠全长与头体长之比为0.44～0.91,是迄今为止报道的无尾两栖类中最小的。     

Novel antimicrobial peptides isolated from the skin secretions of Hainan odorous frog, Odorrana hainanensis

Long time geographical isolation of Hainan Island from the China continent has resulted in appearance of many novel frog species. As one of them, Hainan odorous frog, Odorrana hainanensis possesses some special antimicrobial peptides distinct from those found in other Odorrana. In this study, three antimicrobial peptides have been purified and characterized from the skin secretion of O. hainanensis. With the similarity to the temporin family, two peptides are characterized by amidated C-terminals, so they are named as temporin-HN1 (AILTTLANWARKFL-NH₂) and temporin-HN2 (NILNTIINLAKKIL-NH₂). The third antimicrobial peptide belongs to the brevinin-1 family which is widely distributed in Eurasian ranids, and thus, it is named as brevinin-1HN1 (FLPLIASLAANFVPKIFCKITKKC). Furthermore, after sequencing 68 clones, eight cDNAs encoding antimicrobial peptide precursors were cloned from the skin-derived cDNA library of O. hainanensis. These eight cDNAs can encode seven mature antimicrobial peptides including the above three, as well as brevinin-1V, brevinin-2HS2, odorranain-A6, and odorranain-B1. Twelve different species of microorganisms were chosen, including Gram-positive, Gram-negative and fungi, to test the antimicrobial activities of temporin-HN1, temporin-HN2, brevinin-1HN1, brevinin-1V, and brevinin-2HS2. The result shows that, in addition to their activities against Gram-positive bacteria, temporin-HN1 and temporin-HN2 also possess activities against some Gram-negative bacteria and fungi. However, the two antimicrobial peptides, brevinin-1HN1 and brevinin-1V of the brevinin-1 family have stronger antimicrobial activities than temporin-HN1 and temporin-HN2 of the temporin family. Brevinin-1HN1 possesses activity against Staphylococcus aureus (ATCC25923), Rhodococcus rhodochrous X15, and Slime mould 090223 at the concentration of 1.2 μM.     

花臭蛙消化道6种激素阳性细胞的免疫组织化学定位

目的应用6种胃肠激素抗血清对花臭蛙（Rana schmackeri）消化道激素阳性细胞进行了免疫组织化学定位。方法SP（Streptavidin peroxidase）免疫组织化学法。结果五羟色胺阳性细胞在消化道各段都有分布,以胃幽门部密度最高,胃体其次,食道和直肠较少;生长抑素阳性细胞主要分布于胃和小肠,其中幽门部较多,食管和直肠未见分布。胃泌素阳性细胞只在十二指肠和空肠两个部位检测到。而胰多肽、胰高血糖素和P-物质阳性细胞在消化道各段均未见其分布。结论花臭蛙消化道这六种内分泌细胞分布与其他两栖类动物比较,既显示了两栖类动物在生活习性及动物消化生理方面消化道激素阳性细胞分布的某些共性,又显示了不同物种在消化道的结构特点、生活环境、食性等方面存在的种间差异。     

湖南省花臭蛙复合体分类及分布格局

运用形态特征系统聚类和分子系统学分析,研究先前报道的湖南省花臭蛙(Odorrana schmackeri)各地理种群的分类组成及其分布格局。结果显示,原认定的花臭蛙湖南省各地理种群已分化为花臭蛙和黄岗臭蛙(O.huanggangensis)两个物种。分布于湘西南及南部雪峰山和南岭的花臭蛙种群应修订为黄岗臭蛙,为湖南省臭蛙属物种新发现,湘西北及湘东南罗霄山脉的种群为花臭蛙,黄岗臭蛙与花臭蛙在张家界市武陵源景区同域分布。湘西北武陵山与雪峰山之间以及湘中丘陵地带花臭蛙种群的分类归属,黄岗臭蛙和花臭蛙在湖南省分布格局的形成以及同域分布的机制值得探讨。     

Characterization of an insulinotropic peptide from skin secretions of Odorrana andersonii

Insulinotropic peptide agents are regarded as potential candidates for anti‐diabetic treatment. In the present study, a novel insulinotropic peptide, termed OA‐A1, was purified from frog skin secretions of Odorrana andersonii. Mature OA‐A1 was determined to be a 1965.049 Da peptide with an amino acid sequence of LVGKLLKGAVGDVCGLLPIC, in which an intramolecular disulfide bridge was formed by two cysteine residues. At the cellular level, OA‐A1 exhibited potent proliferation promoting effects on mouse‐derived pancreatic β‐TC‐6 cells and significantly stimulated insulin release in β‐TC‐6 cells at a minimum concentration of 1 nM. In the animal model, OA‐A1 also showed a dose‐dependent insulin‐releasing role in mice. At concentrations ranging from 1 nmol/kg to 1 μmol/kg, OA‐A1 had a significant acute hypoglycemic effect on streptozotocin (STZ)‐induced diabetic mice. The pancreatic islet areas of diabetic mice increased dose‐dependently after 21 days of OA‐A1 treatment (1–100 nmol/kg) compared with those of the saline control group. Moreover, OA‐A1 significantly improved the oral glucose tolerance of STZ‐induced diabetic mice. Taken together, these results suggest that OA‐A1 provides an excellent template for the development of novel anti‐diabetic therapeutic agents. Copyright © 2017 European Peptide Society and John Wiley & Sons, Ltd.