Tyrosine hydroxylase activity and dopamine turnover of rainbow trout (Oncorhynchus mykiss) brain: the special status of the hypothalamus

The dynamics of catecholamine (CA)-synthesis enzymes have been poorly studied in fish. Tyrosine hydroxylase (TH), the rate-limiting enzyme of CA synthesis has been only studied inin vitro conditions. In the present report thein vivo CA synthesis and the CA metabolism were studied in different regions of the forebrain of the rainbow trout. Levels of norepinephrine (NE), dopamine (DA), 3,4-dihydroxyphenylacetic acid (DOPAC) and the rate of accumulation of 3,4-dihydroxyphenylalanine (DOPA) were determined by HPLC following a treatment with hydroxybenzylhydrazine (NSD), a potential inhibitor of DOPA decarboxylase. Kinetics of the accumulation of DOPA and of the decline of DOPAC were in agreement with those found in rat, evidencing that the accumulation of DOPA following NSD can be used in trout to quantify thein vivo enzymatic activity of tyrosine hydroxylase. Experiments using treatment with NSD or with methyl-p-tyrosine reached a same conclusion: the DA neuronal activity in trout is much higher than NE neuronal activity. However, the hypothalamus had high DA levelsvs. lowin vitro andin vivo TH activities and exhibited a low CA turnover.     

Lectin binding patterns in the olfactory bulb of mallard ducks (Anas platyrhynchos)

We histologically examined lectin binding patterns in the olfactory bulb of mallard ducks (Anas platyrhynchos) using 21 biotinylated lectins. Positive staining for the N‐acetylglucosamine‐specific lectins (Bandeiraea simplicifolia II, Datura stramonium, Lycopersicon esculentum, Solanum tuberosum, Triticum vulgare), galactose or N‐acetylgalactosamine‐specific lectins (Artocarpus intergrifolia, Phaseolus vulgaris erythroagglutinin, Phaseolus vulgaris leucoagglutinin, Ricus communis) and the mannose‐specific lectins (Lens culinaris and Pisum sativum) was observed in the olfactory nerve and glomerular layers. Canavalia ensiformis staining showed a similar pattern to that obtained with the lectins and there was also faint staining in the mitral cells. Olfactory nerve axons terminate in the glomeruli, where they make excitatory synapses with the dendrites of mitral cells. This finding indicates that glycoconjugates that bind Canavalia ensiformis play an important role in formation of glomeruli. No positive staining for the other lectins was seen in the olfactory bulb. Based on these results, we conclude that cell surface sugar moieties of the olfactory bulb in mallard ducks express N‐acetylglucosamine and mannose residues rather than N‐acetylgalactosamine residues. The carbohydrate composition of mallard duck olfactory bulb differed from that of other vertebrates found in previous studies.     

仔猪嗅球区和球后区的细胞构筑

用冰冻切片和石蜡切片、Kluver-Barrera 染色法研究了60日龄仔猪脑的嗅球区和球后区。发现猪的嗅球和副嗅球是典型的哺乳动物构造。副嗅球位于嗅球的背内侧,呈长椭圆形,长约2mm。嗅脚内的前嗅核各部细胞群的位置和形状与通过嗅球界沟的平面和嗅脚向前伸向背外侧方的位置有关。嗅脚的背外侧较长,其内的前嗅核细胞群较长;嗅脚的腹内侧较短,其内的细胞群也较短。前嗅核的细胞由分化程度较少的中、小型细胞组成。前嗅核外侧部、背侧部和内侧部与相邻的皮质连续,其细胞排列也类似于皮质的分层结构。前嗅核内侧部的浅层有前海马皮质延伸来的锥体细胞,前海马皮质在嗅脚基部的内侧形成小隆起突出于脑表面。前嗅核外部的细胞群是“C”形带状,贴于与嗅球界沟邻接的纤维束,细胞较小。     

磁场抑制洋葱鳞茎萌发的生理机制的研究

分别用4个强度的恒定磁场对紫皮洋葱鳞茎进行不同时间的处理。结果表明：一定强度的恒定磁场和处理时间可以降低洋葱鳞茎可溶性蛋白质含量、可溶性糖含量、总淀粉酶活性，提高IAA氧化酶的活性，从而抑制洋葱鳞茎的发芽；可溶性蛋白质含量、可溶性糖含量、总淀粉酶活性与洋葱鳞茎发芽率的高低呈正相关关系，而IAA氧化酶活性与洋葱鳞茎发芽率的高低呈负相关关系。     

醚菌酯对百合鳞茎青霉病的控制

采用醚菌酯浸泡兰州百合青霉病的研究结果表明:在25~100 mg/L处理浓度范围内,醚菌酯可明显降低损伤接种圆弧青霉(Penicillium cyclopium)在百合鳞片体内的扩展,其中以50 mg/L处理的效果最好,100 mg/L和125mg/L处理均造成了一定程度的药害.不同温度处理结果显示,40℃的醚菌酯处理效果优于其他温度处理,50℃和60℃处理均产生了严重的烫伤.损伤接种与药物处理的间隔时间也会对处理结果造成一定的影响.     

乌鳢嗅觉器官发育的组织学研究

采用组织学方法对乌鳢仔鱼(全长14～31mm)和咸鱼(全长370mm)嗅觉器官的发育进行了研究。结果表明：乌鳢嗅觉器官由头部左右两侧的嗅囊构成,每个嗅囊有前后2个鼻孔。随其发育,仔鱼前鼻孔隆起于外表面。发育为管状延伸物而与外界相通。嗅板在嗅囊内发育时不形成中心脊,其排列方式为纵向平行的D型。从仔鱼发育至咸鱼,乌鳢嗅觉上皮的厚度变化较小,而初级嗅板的数量和隆起高度显著增大。嗅觉上皮主要由感受细胞、支持细胞、纤毛细胞和基细胞组成。     

北方山溪鲵嗅觉感受器的组织结构

用光镜观察了北方山溪鲵(Batrachuperus tibetanus)幼体和成体鼻腔的组织结构。结果显示,北方山溪鲵幼体和成体的嗅上皮中均存在Bowman′s腺,鼻腔外侧存在犁鼻器。山溪鲵属于有尾目中最原始的类群,为终生水栖型。说明在四足动物从水生到陆生的演化过程中,嗅黏膜中Bowman′s腺的出现与陆生环境没有直接关系。山溪鲵具有犁鼻器,说明在水生型的原始有尾两栖动物已经具有犁鼻器,犁鼻器在种系发生上是从水生的四足动物出现的。     

Eucharis Grandiflora Planch. and Linden Development Fertirrigated with Different Osmotic Potentials

Eucharis grandiflora Planch. and Linden is a tropical climate Amaryllidacea, commonly known as lily, which develops a bulbous stem and is considered an indoor ornamental plant for its evergreen foliage and inflorescence. The aim of this study was to evaluate the vegetative development of the Lily, in response to the treatment with of the Steiner solution at different concentrations. The plants were acclimated under greenhouse conditions and the bulbs selected by a completely randomized design. Plants were treated with various concentrations of the Steiner solution, to develop the following potential osmotic: ?0.018, ?0.036, ?0.054, ?0.072, and 0 Mpal. The production of bulbils, development and leaf area, stomatal density, chlorophyll quantification, and osmotic potentials were evaluated. The results showed that treatment with solutions of ?0.054 and ?0.072 MPa induced a greater vegetative growth, 29.5% more stomata developed, and synthesized 29% more chlorophyll “b” than the control.     

稀土元素在中国水仙上的应用研究

1982～1985年的小区试验及扩大示范试验表明:稀土元素能促进中国水仙出苗、展叶、叶片生长、叶绿素增加;并能促进磷茎膨大、增加大花球百分率而提高大花球产量;同时对改善中国水仙品质、增加花葶数也有良好的作用。三年定点小区试验结果:采用浸种配合喷施处理的效果优于单独浸种或单独喷施的处理。最佳处理组合:低浓度浸种配合初苗期和壮球期用低浓度喷叶,大花球百分率最高。三年平均:磷茎围径≥24cm 和22～23.9cm 的大花球,最佳处理组合为14.5%和40.5%,比对照的8.6%和32.6%分别增加67.6%和24.2%。平均花葶数,最佳处理组合为4.1葶/粒,比对照的3.6葶/粒增加13.9%。扩大示范试验的结果表明:磷茎围径≥24cm 的大花球,稀土处理为58.0%,比对照的48.0%增加20.8%;平均花葶数,稀土处理为4.7葶/粒,比对照的4.4葶/粒增加6.8%。中国水仙施用稀土,由于提高了大花球产量和增加了花葶数,从而能显著地提高经济效益。每公顷可增加产值7500元以上,即增加产值9.7%以上。     

4种单体化合物对甜菜夜蛾嗅觉行为的影响

利用Y型嗅觉仪测定方法,研究了己酸、壬酸、己醇和壬醛4种单体化合物对甜菜夜蛾嗅觉行为的影响,并对4种化合物的有效剂量进行了筛选。结果表明,4种供试化合物均对甜菜夜蛾雌虫表现出明显的驱避作用。己酸的驱避活性剂量范围为稀释200～1 200倍,壬酸的有效剂量范围为稀释10～1 000倍,己醇在稀释300倍和500倍时表现出显著的驱避活性,而壬醛在稀释800～1 200倍时对甜菜夜蛾雌虫有显著的驱避作用。己酸、壬酸、己醇和壬醛驱避效果最佳的稀释倍数分别为1 000倍、500倍(和800倍)、500倍、1 000倍,驱避率依次为96%、82%、76%、82%。因此,这4种对甜菜夜蛾具有明显抑制作用的单体化合物在甜菜夜蛾的防治方面有潜在的应用前景。