阿维菌素对黑斑侧褶蛙毒理效应的研究

本文选用生物农药阿维菌素作为染毒试剂,以农田中常见黑斑侧褶蛙Pelophylax nigromaculatus为研究对象,分别从急性毒性、亚急性毒性、遗传毒性和生理毒性四个方面的实验综合探讨了阿维菌素对黑斑侧褶蛙的生态毒理学效应。急性毒性实验结果表明,阿维菌素对黑斑侧褶蛙24h、48h、72h、96h的LC50分别为:0.3227mg/L、0.0966mg/L、0.0623mg/L、0.0432mg/L,其对黑斑侧褶蛙的安全浓度(SC)为0.004316mg/L。亚急性毒性实验结果表明,暴露期间,随着浓度的升高,毒害作用越大,其对黑斑侧褶蛙肝脏组织损害也越大,而经恢复期后,各实验组肝脏组织受损程度较暴露期都有降低。红细胞核异常及微核诱导实验结果表明,微核和核异常现象与阿维菌素浓度的相关性有一定的范围;随着时间的延长,红细胞核异常率及微核率先上升后下降。肝脏LDH同工酶聚丙烯酰胺凝胶电泳实验结果表明,在一定时间条件下,随浓度的升高,LDH1和LDH2酶带活性呈现降低趋势,LDH4酶带活性无明显变化,LDH5酶带活性先升高后再降低,在同一浓度条件下,随着时间的延长,肝脏LDH同工酶活性均呈升高的趋势。实验结果表明阿维菌素对黑斑侧褶蛙能够造成不同程度的生理、病理及遗传性损伤。     

壬基酚对雄性黑斑蛙生殖毒性的研究

通过研究壬基酚对雄性黑斑蛙(Rana nigromaculata)成体的精子和精巢的影响,探讨壬基酚对黑斑蛙的生殖毒性.用不同剂量的壬基酚对雄性黑斑蛙进行处理,对黑斑蛙的精巢系数、精子数、形态结构、畸形率和精巢显微结构等分别进行研究.结果表明,与对照组相比,随着壬基酚浓度的升高,染毒组黑斑蛙的精巢系数下降,精子数减少,精子畸形率明显增大;畸形精子主要表现为其头部出现肥大、弯曲和圆形等现象;精巢显微结构发生变化,表现为生精小管萎缩,生精细胞层次减少,间质区不明显.说明壬基酚对雄性黑斑蛙生殖系统具有毒性效应.     

几种农药对黑斑蛙黑斑蛙胚胎及蝌蚪的毒性

本文报道了常用的几种农药对黑斑蛙胚胎及蝌蚪发育的毒性影响。结果表明 :农药对黑斑蛙胚胎、蝌蚪期的毒性大小依次为使它隆 >多效唑 >多菌灵 >异丙隆 >甲胺磷。胚胎期死亡时表现为胚体腐烂 ;蝌蚪期死亡时则表现为头部膨大 ,尾部缩小 ,弯曲。畸形在两个时期都表现为腹部膨大呈透明状和尾部弯曲     

壬基酚对黑斑蛙神经活动的影响

应用电生理的方法研究不同浓度壬基酚对黑斑蛙的坐骨神经干神经冲动产生和传导的影响。用不同浓度的壬基酚处理黑斑蛙,7 d后,观察其活动状态和体表特征,同时用生物信号采集处理系统分别测定壬基酚对黑斑蛙坐骨神经干的神经冲动传导速度、动作电位幅度、相对不应期和绝对不应期的影响。结果表明：随着壬基酚浓度的增加,黑斑蛙的活力减弱,其皮肤出现血斑的现象加重,说明壬基酚可引起黑斑蛙活力、精神和体表等发生异常;随着壬基酚浓度的升高,黑斑蛙坐骨神经干的神经冲动传导速度逐渐减慢,动作电位峰值降低,相对不应期和绝对不应期逐渐延长,与壬基酚浓度呈剂量-效应关系。说明在壬基酚作用下,黑斑蛙神经活动对刺激反应的灵敏性降低,动作电位的产生及传导受到一定程度的抑制和阻碍。在50 mg·kg^-1低浓度组,壬基酚对黑斑蛙神经活动影响不显著(P>0.05),说明黑斑蛙对低浓度的壬基酚有一定的耐受力。     

几种农药对黑斑蛙胚胎及蝌蚪的毒性

本文报道了常用的几种农药对黑斑蛙胚胎及蝌蚪发育的毒性影响。结果表明：农药对黑斑蛙胚胎、蝌蚪期的毒性大小依次为使它隆＞多效唑＞多菌灵＞异丙隆＞甲胺磷。胚胎期死亡时表现为胚体腐烂;蝌蚪期死亡时则表现为头部膨大,虱部缩小,弯曲。畸形在两个时期都表现为腹部膨大呈透明状和尾部弯曲。     

3种无尾两栖类肾形态结构及其对环境的适应性

从显微和亚显微结构以及酸性磷酸酶组织化学等方面,比较研究了史氏蟾蜍(Bufo stejnegeri)、黑斑侧褶蛙(Pelophylax nigrontaculata)和中国林蛙(Rana chensinensis)肾实质,尤其是肾单位的结构特点.3种动物在非繁殖期活动于不同的生境类型,黑斑褶摺蛙属于水生类型,而史氏蟾蜍...     

壬基酚对黑斑蛙的毒性效应

通过研究壬基酚对黑斑蛙(Rana nigromaculata)血浆渗透压以及血细胞的影响,探讨壬基酚对黑斑蛙血液的毒性效应。用200、400和600mg/kg壬基酚分别对黑斑蛙腹部淋巴囊注射染毒,在不同的时间间隔内利用渗透压仪测量各组血浆渗透压,同时制作血涂片观察血细胞的异常现象。结果表明,在相同处理时间内,随着壬基酚浓度的增加,黑斑蛙血浆渗透压值上升,血细胞膨大,血细胞核分裂以及核质不均匀现象明显;在相同浓度处理组中,随着处理时间的延长,黑斑蛙血浆渗透压上升,血细胞膨大,细胞核损害严重。壬基酚可诱发红细胞出现微核现象,随着壬基酚浓度的增加,同一处理时间内黑斑蛙红细胞微核及核异常率呈现先上升后下降的变化规律;随着处理时间的延长,各处理组红细胞微核率及核异常率呈现下降的趋势。     

黑斑蛙嗅器和犁鼻器的组化及超微结构特征

嗅感受器主要感知外界环境中化学信号分子.本文采用银染、NADPH-组化染色和电镜技术来观察黑斑侧褶蛙(Petophylax nigromaculatus)的嗅器和犁鼻器的功能差异及细胞组成.银染法可对嗅上皮和犁鼻上皮的细胞进行分类及区分.其中,支持细胞胞核深染成黑色,嗅细胞胞核银染为花斑状.细胞计数显示,犁鼻上皮的嗅神经细胞含量百分比显著高于嗅上皮.组化结果显示,黑斑侧褶蛙嗅上皮和犁鼻上皮对NADPH-d表达模式差异显著,前者表达明显高于后者.电镜结果显示,黑斑侧褶蛙嗅上皮和犁鼻上皮的支持细胞由两种类型的细胞组成,分别为纤毛型和颗粒型支持细胞.     

重金属离子对黑斑蛙胚胎及蝌蚪的毒性影响

本文研究了5种重金属对黑斑蛙胚胎期及蝌蚪期的毒性作用,结果表明,各重金属离子对胚胎期中的孵化期和开口期毒性较大,其余各期毒性较小。各重金属离子对胚胎的毒性顺序为Hg     

上海郊野公园无尾两栖动物微生境利用特征研究

两栖动物是衡量城市生态系统环境质量的指标类群。郊野公园是上海城市生态系统中重要的两栖类栖息地。2015年5—9月,采用样线法对上海市6个郊野公园的无尾两栖类物种种群数量进行调查,采用样方法采集15种微生境变量数据。通过主成分分析和冗余分析了解各无尾两栖类物种对微生境因子的利用特征,并用卡方适合度检验分析无尾两栖类的不同种间分布重叠度。结果表明,优势度由高到低为泽陆蛙Fejervarya multistriata、金线侧褶蛙Pelophylax plancyi、中华蟾蜍Bufo gargarizans、饰纹姬蛙Microhyla fissipes、黑斑侧褶蛙P.nigromaculatus,适宜的水质和结构合理的水生植被是其生存、繁衍的基础,坡度较小的自然坡岸是无尾两栖类自由往返水陆之间的重要保障。陆生植被的重要性次于水生植被,仅与金线侧褶蛙和黑斑侧褶蛙的分布有显著正相关。不同无尾两栖类物种对水体大小的适应能力不尽相同,郊野公园的水体比较开阔,不利于饰纹姬蛙的生存。本研究建议根据不同无尾两栖类的栖息地利用特征,建设具有不同物种特异性的栖息地景观,在保护好无尾两栖类的同时进一步提升公共绿地的综合生态服务效能。     

Investigation of the mechanism of temperature sensitivity of the electroreceptors of ampullae of lorenzini

In experiments on Black Sea skates (Raja clavata), the potential of the receptor epithelium of the ampullae of Lorenzini and spike activity of single nerve fibers connected to them were investigated during electrical and temperature stimulation. Usually the potential within the canal was between 0 and –2 mV, and the input resistance of the ampulla 250–400 k. Heating of the region of the receptor epithelium was accompanied by a negative wave of potential, an increase in input resistance, and inhibition of spike activity. With worsening of the animal's condition the transepithelial potential became positive (up to +10 mV) but the input resistance of the ampulla during stimulation with a positive current was nonlinear in some cases: a regenerative spike of positive polarity appeared in the channel. During heating, the spike response was sometimes reversed in sign. It is suggested that fluctuations of the transepithelial potential and spike responses to temperature stimulation reflect changes in the potential difference on the basal membrane of the receptor cells, which is described by a relationship of the Nernst's or Goldman's equation type.I. P. Pavlov Institute of Physiology, Academy of Sciences of the USSR, Leningrad. I. M. Sechenov, Institute of Evolutionary Physiology and Biochemistry, Academy of Sciences of the USSR, Leningrad. Pacific Institute of Oceanology, Far Eastern Scientific Center, Academy of Sciences of the USSR, Vladivostok. Translated from Neirofiziologiya, Vol. 12, No. 1, pp. 67–74, January–February, 1980.     

Principles of organization and evolution of systems of regulation of functions

Evolution of living organisms is closely connected with evolution of structure of the system of regulations and its mechanisms. The functional ground of regulations is chemical signalization. As early as in unicellular organisms there is a set of signal mechanisms providing their life activity and orientation in space and time. Subsequent evolution of ways of chemical signalization followed the way of development of delivery pathways of chemical signal and development of mechanisms of its regulation. The mechanism of chemical regulation of the signal interaction is discussed by the example of the specialized system of transduction of signal from neuron to neuron, of effect of hormone on the epithelial cell and modulation of this effect. These mechanisms are considered as the most important ways of the fine and precise adaptation of chemical signalization underlying functioning of physiological systems and organs of the living organism