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1.
运用免疫组织化学方法研究了褪黑激素受体亚型Mel1a在大弹涂鱼视网膜、脑部、垂体、松果体、性腺和小肠中的分布.结果表明,Mel1a分布于视网膜的感光细胞层、外丛状层、内核层和神经节细胞层;小脑分子层;视顶盖边缘层和视觉层;垂体的神经垂体和腺垂体的中外侧部;松果体终囊及背囊;精巢的间质细胞、精原细胞、精母细胞以及精子细胞;卵膜的滤泡细胞;小肠的柱状上皮细胞外沿和肌肉层.研究结果提示褪黑激素参与大弹涂鱼多种生理功能的调节,为进一步揭示Mel1a在硬骨鱼体内的分布及其作用提供了科学依据.  相似文献   

2.
应用松果腺细胞改良染色法,证实了黄鳝脑部存在松果腺复合体,光镜及电镜切片的研究结果表明,黄鳝松果腺复合体由终囊,松果体柄和背囊三部分组成;  相似文献   

3.
应用松果腺细胞改良染色法(Achucarro-Hortegastaining),证实了黄鳝脑部存在松果腺复合体。光镜(HE染色)及电镜切片的研究结果表明,黄鳝松果腺复合体由终囊、松果体柄和背囊三部分组成;每部分均包含有类光感细胞、支持细胞及神经节细胞等细胞类型。类光感细胞包括外节、内节、胞体和基突4个组成部分,其形态结构与脊椎动物眼中的光感细胞极其相似。由于类光感细胞中分布有大量的分泌样颗粒,故而推测黄鳝脑部松果腺复合体具有感光与分泌的双重功能。  相似文献   

4.
研究了三种鲻科鱼类的松果体显微、超微结构,并比较了它们的异同;结果表明三种松果体形态各异,但都有三种典型的细胞:感光细胞、支持细胞、神经节细胞.三种鱼都有松果体,但没有背囊.  相似文献   

5.
日本三角涡虫组织结构嗜银反应观察   总被引:1,自引:0,他引:1  
涡虫在动物系统演化史上占有十分重要的地位,雌雄同体,具有很强的再生能力,因此,对其组织结构嗜银反应进行研究具有重要的意义.本文用Grimellus还原银法显示了日本三角涡虫(Dugesia japonica)嗜银反应阳性的组织结构.结果表明:肠上皮细胞内有很多染成棕褐色的圆形泡状结构,肠上皮下的实质组织细胞中分布很多黑色颗粒;交配囊上皮细胞可见染成棕褐色的颗粒;在雄腔和交配囊柄两侧和后部可见染成棕褐色的三角形区域;纵神经索嗜银反应较弱,呈浅褐色.因此,可以确定肠上皮下实质组织中存在APUD系统.  相似文献   

6.
本文详细描述了花斑裸鲤和青海湖裸鲤嗅觉器官的形态结构,并通过其形态特征的异同比较、对嗅觉器官与其生态和习性的关系作了初步探讨.1.这二种鱼嗅器觉官的形态结构十分相似,表明同属鱼有一些共同稳定的特征,可作为分类依据之一.2.嗅觉器官的发达程度与鱼类栖息环境和习性有密切关系.3.这二种鱼有副鼻囊,副鼻囊可能同吸水有关.  相似文献   

7.
应用组织学切片和光镜观察的方法,对南方鲇、革胡子鲇和鲇的脑和延脑上初级味觉中枢组织构筑进行比较研究.结果表明,3种鲇鱼在脑组织构造上具有的共同特点是端脑发达,体积比视顶盖大;小脑特别发达,向前盖住中脑、间脑和部分端脑,向后侧形成耳状叶;间脑有明显的下叶,视交叉紧靠间脑前方,垂体在二下叶之间,远离视神经交叉.而作为鱼类味觉初级中枢的面叶和迷走叶形态结构存在较大差异,显示了作为鱼类味觉初级中枢的延脑,其组织结构的复杂性与摄食行为及其食性之间的关系.  相似文献   

8.
中华绒螯蟹(Eriocheir sinensis)雌性生殖系统的组织学研究   总被引:3,自引:0,他引:3  
以组织切片方法研究中华绒螯蟹雌性生殖系统结构以及卵子发生和卵巢发育的周年变化表明:卵巢壁由外膜及内生殖上皮组成;输卵管壁由外膜及管壁上皮组成;受精囊分为伸展腔和皱缩腔,二者囊壁上皮结构不同,并有周期性变化。卵子发生根据卵细胞、细胞核及核仁的大小形态、核质比(NP)和卵黄积累情况可分为:1.卵原细胞期;2.小生长期;3.大生长期;4.成熟前期和5.成熟期。卵巢发育则根据第一批卵细胞的发育情况、卵巢长度及颜色分为五期,大致可归纳为三个阶段:5~7月为延缓期;8~11月为对数增长期;12~4月为稳定期。  相似文献   

9.
打开鱼体腹腔,一个白色的胶质膜状囊引人注目,大而有弹性,位于肾与消化道之间,这便是鱼类的鳔.并非所有鱼都有鳔,软骨鱼类和少数硬骨鱼类没有鳔.餐桌上的"鱼肚",便是干制鱼鳔烹炸的美味.鳔的形态因不同鱼类而异,又因鳔内分隔的有无而区分为一室鳔、二室鳔和三室鳔.整个鳔的外形,有卵圆形的、圆锥形的、  相似文献   

10.
黑斑蛙松果体由额器和松果体本部两部分组成,额器位于颅骨外,两眼之间皮肤的真皮层内,呈一团致密细胞,其结构和位置与其它变温动物的松果眼不同,缺乏感光结构,光果体本部包括脑旁体和松果体本体,主要成分有光接受细胞,支持细胞,血管和神经纤维。光接受细胞除具有许多和视锥,视杆细胞相似的细胞学特征,如排列不规则的外节,内节和突触成分外;胞质内还含有大量的线粒体,核糖体粗面和滑面内质网,中等量的高尔基复合体及少  相似文献   

11.
A circadian oscillator in cultured cells of chicken pineal gland   总被引:19,自引:0,他引:19  
T Deguchi 《Nature》1979,282(5734):94-96
The activity of serotonin N-acetyltransferase, the key enzyme of melatonin synthesis, shows a marked circadian rhythm in the pineal glands of various animal species. The regulation mechanism of the N-acetyltransferse rhythm in birds is different from that in mammals. N-Acetyltransferase activity in rat pineal gland is controlled by the central nervous system through the sympathetic nerves from the superior cervical ganglion, while in chicken the endogenous oscillator for N-acetyltransferase rhythm is presumably located in the pineal gland. Recently it has been shown that N-acetyltransferase activity oscillates in a circadian manner in the organ culture of chicken pineal glands. When chicken pineal glands were organ-cultured under continuous illumination, the nocturnal increase of enzyme activity was suppressed. These observations suggested that chicken pineal gland contains a circadian oscillator, a photoreceptor and melatonin-synthesising machinery. A central question arises whether the circadian oscillation of N-acetyltransferase activity and its response to environmental lighting are generated within the cell or are emergent properties of interaction between different types of pineal cells. I report here that in the dispersed cell culture of chicken pineal gland, N-acetyltransferase activity exhibits a circadian rhythm and responds to environmental lighting in the same manner as in the organ culture.  相似文献   

12.
为了研究蟾蜍松果体的形态特征,并了解松果体在生物节律中所起的作用,运用常规的光镜样品制备技术,对松果体的细胞形态及其在冬眠期、非冬眠期的变化进行了观察.研究结果显示,松果体的额器及脑上体都具有与视网膜感光细胞相似的细胞,称之为类光感细胞,因而它们具有感受光的能力;同时,根据细胞结构的观察以及两者所处位置的不同,认为额器具有比脑上体更强的感光性能.通过冬眠期与非冬眠期的细胞形态学比较,可以看到额器及脑上体的类光感细胞外节均有较明显的变化.冬眠期可见额器的类光感细胞外节排列规则,但数量减少,而脑上体的类光感细胞外节排列明显不规则,内有很多小泡,呈退化状态.额器及脑上体支持细胞的细胞质和类光感细胞线粒体的形态在冬眠扨亦有一定的变化.实验结果表明,额器及脑上体感光性能在冬眠期与非冬眠期是有差异的,脑上体在冬眠斯进入退化状态。  相似文献   

13.
本文采用光镜和透射电镜,对日本七鳃鳗,黑斑蛙和丽斑麻蜥4种变动物的松果腺复合体,进行了观察和比较,并对其结构与功能的关系作了初步探讨,变温动物的松果腺复合体,由副松果体和松果体构成,在系统发育中,副松果体始终是光感受器,松果体则从光感觉器向着内分泌腺发展,从这4种动物松果腺复合体的变化揭示;最早脊椎动物的松果眼是2个,以后在动物从低等向高等进化中,其中一个保留在变温动物,始终是光感觉器,另一个变成  相似文献   

14.
S D Wainwright 《Nature》1980,285(5765):478-480
Levels of serotonin N-acetyltransferase (NAT: acetul CoA:arylamine N-acetyltransferase; EC 2.1.1.5.) activity in the chick pineal gland exhibit a marked diurnal variation in birds kept under a diurnal cycle of ilumination. Activity begins to rise rapidly at the start of the dark phase of the cycle and reaches maximum levels at mid-dark phase about 25-fold greater than the minimum basal level at mid-light phase. Thereafter, the level of activity declines to the basal level about the start of the light phase. This diurnal cycle in chick pineal NAT activity found in vivo has recently been reproduced in vitro with intact glands incubated in organ culture. The mechanism of the 'biological clock' which regulates these variations in level of chick pineal NAT activity is unknown. However, I now report that chick pineal glands cultured under a diurnal cycle of illumination exhibit a diurnal cycle in content of cyclic GMP which roughly parallels the cycles in NAT activity. In contrast, there was no correlation between variations in pineal content of cyclic AMP and in level of NAT activity.  相似文献   

15.
16.
本文观察了在生殖季节末期利非生殖季节未期,损毁松果腺的26只树性腺和附性腺重量及组织学的变化.结果发现损毁树松果腺未见影响动物体重.在生殖季节末期损毁树松果腺,未见抑制性腺和附性腺重量减少,但见其在组织学水平上不衰退;在非生殖季节末期损毁树松果腺,未见性腺和附性腺提前增重,但见其在组织学水平上提前恢复.  相似文献   

17.
D Sugden  J Vanecek  D C Klein  T P Thomas  W B Anderson 《Nature》1985,314(6009):359-361
The pineal gland has proven to be an excellent model for the study of adrenergic control systems. Noradrenaline, released from sympathetic nerve terminals in the pineal gland, regulates a large nocturnal increase in melatonin synthesis by stimulating the activity of arylalkylamine N-acetyltransferase (NAT, EC 2.3.1.87) 30-70-fold. An essential step in both the induction and maintenance of high NAT activity is an increase in intracellular cyclic AMP. Noradrenaline acts via beta-adrenoceptors to increase pineal cyclic AMP by activating adenylate cyclase, and the activation of pineal alpha 1-adrenoceptors potentiates beta-adrenergic stimulation not only of NAT but of both cyclic AMP and cyclic GMP. Here we describe investigations designed to test whether alpha 1-adrenergic potentiation of beta-adrenergic stimulation of pineal cyclic AMP involves protein kinase C. Our results suggest that kinase activation is involved and the data provide the first demonstration of a synergistic interaction between Ca2+-phospholipid-dependent protein kinase (protein kinase C) and neurotransmitter-dependent stimulation of cyclic AMP.  相似文献   

18.
S E Dryer  D Henderson 《Nature》1991,353(6346):756-758
Phototransduction in the vertebrate retina is dependent in part on a cyclic GMP-activated ionic channel in the plasma membrane of rods and cones. But other vertebrate cells are also photosensitive. Cells of the chick pineal gland have a photosensitive circadian rhythm in melatonin secretion that persists in dissociated cell culture. Exposure to light causes inhibition of melatonin secretion, and entrainment of the intrinsic circadian oscillator. Chick pinealocytes express several 'retinal' proteins, including arrestin, transducin and a protein similar to the visual pigment rhodopsin. Pinealocytes of lower vertebrates display hyperpolarizing responses to brief pulses of light. Thus it is possible that some of the mechanisms of phototransduction are similar in retinal and pineal photoreceptors. We report here the first recordings of cyclic GMP-activated channels in an extraretinal photoreceptor. Application of GMP, but not cyclic AMP, to excised inside-out patches caused activation of a 15-25 pS cationic channel. These channels may be essential for phototransduction in the chick pineal gland.  相似文献   

19.
褪黑素在抑郁症中的研究   总被引:1,自引:0,他引:1  
褪黑素(MT)是松果腺分泌的主要激素,对机体有着广泛的影响。抑郁症患者MT水平降低、生理节律紊乱。对褪黑素在抑郁症中的研究新进展进行了综述。  相似文献   

20.
草原沙蜥顶眼的角膜是由位于顶眼部位的皮肤特化形成,皮肤细胞色素消失,外表面的立方形细胞变为扁平细胞,其下的基质逐渐增厚,纤维增多,透明成角膜。晶状体与角膜紧密相贴,由交错排列的的几层柱状细胞组成,视网膜和晶状体相连,由感光细胞,色素细胞和神经节细胞组成,在由晶状体和视网膜围成的眼腔中,有玻璃体样结构分布,偶见有散在的细胞位于玻璃体样结构中。  相似文献   

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