Distribution of α-MSH-like immunoreactive cells in the nervous system, Hatschek''''s pit and other tissues of amphioxus, Branchiostoma belcheri

Immunohistochemical localization of a-melanocyte-stimulating hormone (α-MSH) in the nervous system, Hatschek's pit and other tissues of amphioxus (Branchiostoma belcheri) was performed using the antibody against synthetic α-MSH. The results revealed that α-MSH-like immunoreactive cells were distributed at the dorsal side and ventral side of brain vesicle, the dorsal side and the surrounding of nerve tube, and in the epithelial cells of Hatschek's pit, the zone 1, 3, and 6 of endostyle and gut. The immunoreactive substance was also found in the primary oocytes of the small and large growth stage of ovary and early stage spermatogenic cells in testis. These findings indicate that α-MSH is an ancient and highly conserved hormone and it is extensively distributed in amphioxus. Although Hatschek's pit in amphioxus does not have a structure of the intermediate lobe of vertebrate adenohypophysis, it has already hosted α-MSH-like endocrine cells, implying that the functional differentiation of α-MSH-like cells occurred earlier than the differentiation of the tissue structure. The results of the present study provided a new evidence for the endocrinology of Hatschek's pit and for the origin and evolution of vertebrate adenohypophysis.     

Distribution of growth hormone-like immunoreactive cells and somatostatin receptors in the nervous system and Hatschek's pit of amphioxus, Branchiostoma belcheri

Using immunohistochemical method and double staining technique, the localization of growth hormone (GH) and somatostatin receptors in the nervous system and Hatschek's pit of amphioxus has been investigated. The results showed that the growth hormone-like nerve cells and endocrine cells as well as three subtypes of somatostatin receptors exist in the nervous system and Hatschek's pit, and GH-like nerve cells and endocrine cells co-exist with three subtypes of somatostatin receptors in the brain vesicle and Hatschek's pit. It is suggested that a primitive control system of inhibitory growth hormone secretion in Hatschek's pit could have been developed in amphioxus, as in vertebrates. The present study provides new evidence for the endocrinology and the evolution of Hatschek's pit.     

Distribution of CRH-and ACTH-like immunoreactive cells in amphioxus,Branchiostoma belcheri

Immunocytochemical studies on the nervous system,Hatschek's pit,digestive tract and gonads tissues of an amphioxus(Branchiostoma belcheri)were performed using polyclonal antibodies against human corticotrophin-releasing hormone(CRH)and human adrenocorticotropin(ACTH).The results showed that many CRH-like immunoreactive neurons were distributed specifically on the dorsal side and ventral side of brain vesicle,while a few CRH-like neurons and their fibers in spinal cord.At the same time,the epithelial cells in the basic region of Hatschek's pit were shown immunopositive to CRH antibody.In gonads(ovary and testis),CRH-immunopositive substance was localized in the cytoplasm near oocyte nucleus and in early spermatogenic cells.ACTH-like immunoreactivities were observed specially in the neurons and their protrusions localized on the ventral side of the brain vesicle and in spinal cord,and also in epithelial cells of Hatschek's pit,enteric neurons of digestive tract,oocytes in ovary and in early spermatogenic cells as well.It was found for the first time that CRH-like neurons existed in the middle region of brain vesicle(corresponding to the hypothalamus of vertebrates)and ACTH-like immunopositive cells existed in Hatschek's pit,implying that a control mechanism between brain vesicle and Hatschek's pit maybe had been already built in amphioxus as that in vertebrates.The present study will provide new morphological evidence for the origin and evolution of ACTH.In addition,the immunoreactivities of CRH and ACTH in the digestive tract and gonads suggested other physiological function of CRH and ACTH in amphioxus.     

Distribution of growth hormone-like immunoreactive cells and somatostatin receptors in the nervous system and Hatschek''s pit of amphioxus, Branchiostoma belcheri

Using immunohistochemical method and double staining technique, the localization of growth hormone (GH) and somatostatin receptors in the nervous system and Hatschek's pit of amphioxus has been investigated. The results showed that the growth hormone-like nerve cells and endocrine cells as well as three subtypes of somatostatin receptors exist in the nervous system and Hatschek's pit, and GH-like nerve cells and endocrine cells co-exist with three subtypes of somatostatin receptors in the brain vesicle and Hatschek's pit. It is suggested that a primitive control system of inhibitory growth hormone secretion in Hatschek's pit could have been developed in amphioxus, as in vertebrates. The present study provides new evidence for the endocrinology and the evolution of Hatschek's pit.     

Distribution of ghrelin-like immunoreactive cells in amphioxus, Branchiostoma belcheri – A study of immunohistochemistry

The distribution of ghrelin-like immunoreactive cells in amphioxus （Branchiostoma belcheri） was investigated by using immunohistochemical staining with rabbit antiserum against synthetical mammalian ghrelin. The results showed that ghrelin-like immunoreactive cells were distributed widely in the nervous system, Hatschek＇s pit, wheel organ, digestive tract and gonads （ovary and testis）. In nervous system, ghrelin-like immunoreactive neurons and their protrusions were distributed specifically on the dorsal side, ventral side and funnel part of brain vesicle, with a few dispersive immunoreactive nerve cells and their fibers in nerve tube. Ghrelin-like immunoreactivities were also detected in Hatschek＇s pit epithelial cells and wheel organ cells, with positive substance located along cell membrane. In digestive tract, ghrelin-like immunoreactive cells existed in hepatic diverticulum, anterior and posterior region of midgut, and could be classified into two types, closed- and opened-type endocrine cells. The number of positive cells was most in hepatic diverticulum, secondary in posterior region of midgut and least in anterior region of midgut. In gonads, ghrelin-like immunoreactive substance was detected in oogonia, oocytes and follicle cells in ovary at the small and large growth stages and in early spermatogenic cells and Sertoli cells in testis. The extensive distribution of ghrelin-like cells in amphioxus suggested that these kinds of cells are conservative in evolution and diversified in function. At the same time, we found for the first time that ghrelin-like immunoreactive cells existed in brain vesicle and Hatschek＇s pit, which provided new morphological evidence for the existence of an activation pathway between brain vesicle and Hatschek＇s pit for the regulation of growth hormone excretion.     

mmunohistochemical localization of gonadotropin-releasing hormone receptors (GnRHR) in the nervous system, Hatschek's pit and gonads of amphioxus, Branchiostoma belcheri

Using gonadotropin-releasing hormone (GnRH) anti-idiotypic antibodies and APA im-munohistochemical method, the immunoreactivity of GnRHR in the nervous system, Hatschek's pit and gonads of amphioxus has been located. It is found for the first time that the immunoreactivity of GnRHR exists in the nerve cells and fibers in the amphioxus's brain and nerve tube and the epithelial cells of Hatschek's pit at the different stages of gonadal development. At the same time, it is also found that GnRHR also exists in the ovary and testis of different developed stages. These findings provide morphological new proof for the informative transfer and regulation between brain and Hatschek's pit mediation by GnRHR, and for the understanding of the mechanism of action on the reproductive endocrine control axis among brain-Hatschek's pit-go-nads.     

Distribution of growth hormone-like immunoreactive cells and somatostatin receptors in the nervous system and Hatschek''''s pit of amphioxus, Branchiostoma belcheri

Using immunohistochemical method and double staining technique, the localization of growth hormone (GH) and somatostatin receptors in the nervous system and Hatschek's pit of amphioxus has been investigated. The results showed that the growth hormone-like nerve cells and endocrine cells as well as three subtypes of somatostatin receptors exist in the nervous system and Hatschek s pit, and GH-like nerve cells and endocrine cells co-exist with three subtypes of somatostatin receptors in the brain vesicle and Hatschek s pit. It is suggested that a primitive control system of inhibitory growth hormone secretion in Hatschek s pit could have been developed in amphioxus, as in vertebrates. The present study provides new evidence for the endocrinology and the evolution of Hatschek's pit.     

Immunohistochemical localization of gonadotropin-releasing hormone receptors (GnRHR) in the nervous system, Hatschek’s pit and gonads of amphioxus,Branchiostoma belcheri

Using gonadotropin-releasing hormone (GnRH) anti-idiotypic antibodies and APA immunohistochemical method, the immunoreactivity of GnRHR in the nervous system, Hatschek’s pit and gonads of amphioxus has been located. It is found for the first time that the immunoreactivity of GnRHR exists in the nerve cells and fibers in the amphioxus’s brain and nerve tube and the epithelial cells of Hatschek’s pit at the different stages of gonadal development. At the same time, it is also found that GnRHR also exists in the ovary and testis of different developed stages. These findings provide morphological new proof for the informative transfer and regulation between brain and Hatschek’s pit mediation by GnRHR, and for the understanding of the mechanism of action on the reproductive endocrine control axis among brain-Hatschek’s pit-gonads.     

Localization and expression of LHβmRNA in the brain and Hatschek's pit of amphioxus, Branchiostoma belcheri

To determine whether gonadotropin-like substance in the brain and Hatschek' s pit of amphioxus issynthesized by the tissue in situ or transported from other tissue, a histochemical study was carried out by in situ hy- bridization using digoxigenin (DIG)-labelled LHβRNAprobes. The results showed that LHβmRNA expressed in the nerve cells of brain and the epithelial cells of Hatschek' s pit, thus providing new evidence for the homology of pituitary of ver- tebrates with Hatschek' s pit and the functional evolution of gonadotropin.     

Effects of damage of Hatschek’s pit of amphioxus on its structure and function

It is found for the first time that, after the structure and endocrine function of Hatschek’s pit ofBranchiostoma belcheri are damaged by monosodium glutamate (MSG) treatment in breeding season, the ovulation of mature ovary, as well as the development of both ovary and testis of large-growth stage are obstructed and stagnated; and in non-breeding season, the process of gonadal development is delayed. The disturbed ovulation and gonadal development can definitely be restored with exogenous gonadotropic hormone as the therapeutical substitute. These results may provide new proof for the complete understanding of the evolutional process of pituitary function in vertebrates and playing an important role in the reproductive endocrine control system of Hatschek’s pit of amphioxus.     

Thyrotrophin in the pars tuberalis triggers photoperiodic response

Molecular mechanisms regulating animal seasonal breeding in response to changing photoperiod are not well understood. Rapid induction of gene expression of thyroid-hormone-activating enzyme (type 2 deiodinase, DIO2) in the mediobasal hypothalamus (MBH) of the Japanese quail (Coturnix japonica) is the earliest event yet recorded in the photoperiodic signal transduction pathway. Here we show cascades of gene expression in the quail MBH associated with the initiation of photoinduced secretion of luteinizing hormone. We identified two waves of gene expression. The first was initiated about 14 h after dawn of the first long day and included increased thyrotrophin (TSH) beta-subunit expression in the pars tuberalis; the second occurred approximately 4 h later and included increased expression of DIO2. Intracerebroventricular (ICV) administration of TSH to short-day quail stimulated gonadal growth and expression of DIO2 which was shown to be mediated through a TSH receptor-cyclic AMP (cAMP) signalling pathway. Increased TSH in the pars tuberalis therefore seems to trigger long-day photoinduced seasonal breeding.     

Position in the evolution of reproductive endocrine of amphioxus,Branchiostoma belcheri

This review summarizes the recent discoveries of many authors who found that in amphioxus Hatschek’s pit is capable of synthesizing vertebrate gonadotropin-like substance, and that the content of gonadotropin-releasing hormone in the amphioxus’ body shows a positive correlation with the reproductive cycle, and that the sex steroid hormone exists in gonads. Exogenous hormones could promote gonadal development, maturation and reproductive activity in amphioxus. A possible implication might be that the reproductive activity in amphioxus is regulated by reproductive hormones like vertebrate, indicating the existence of primitive reproductive endocrine regulatory axis, brain vesicle-Hatschek’s pit-gonads axis, as compared with regulatory axis of vertebrate. It will provide a new line for establishing the position of reproductive endocrine evolution in lancelet.     

老年慢性肺心病急性发作期的甲状腺功能变化

目的：观察老年肺心病急性发作期患者血清甲状腺激素的变化,并探讨其临床意义。方法：用放射免疫法测定47例老年慢性肺心病急性发作期患者（观测组）及34例同期收治的老年肺炎患者（对照组）血清甲状腺激素（T3、FT3、T4、FT4、rT3）及促甲状腺激素（TSH）水平,并进行比较。结果：观测组血清T3、FT3明显低于对照组（P〈0．05）,rT3水平明显升高（P〈0．01）,T4、FT4轻度下降,但无统计学意义（P〉0．05）,TSH两组比较差异无显著性（P〉0．05o结论：老年慢性肺心病患者血清甲状腺激素的变化对病情判断及预后具有一定临床参考价值。     

Neuropeptide modulation of single calcium and potassium channels detected with a new patch clamp configuration

Calcium channel activity is crucial for secretion and synaptic transmission, but it has been difficult to study Ca2+ channel modulation because survival and regulation of some of these channels require cytoplasmic constituents that are lost with the formation of cell-free patches. Here we report a new patch clamp configuration in which activity and regulation of channels are maintained after removal from cells. A pipette containing the pore-forming agent nystatin is sealed onto a cell and withdrawn to form an enclosed vesicle. The resulting perforated vesicle, formed from pituitary tumour cells, contains Ca2+ and K+ channels. Ca2(+)-activated K+ channels in the vesicle are activated by cyclic AMP analogues, and by a neuropeptide (thyrotropin-releasing hormone) that stimulates phosphatidylinositol turnover and inositol trisphosphate-gated Ca2+ release from intracellular organelles. Thus, the perforated vesicle retains signal transduction systems necessary for ion channel modulation. Functional dihydropyridine-sensitive Ca2+ channels (L-type) are maintained in the vesicle, and their gating is inhibited by thyrotropin-releasing hormone. Hence, this new patch clamp configuration has allowed a direct detection of the single-channel basis of transmitter-induced inhibition of L-type Ca2+ channels. The modulation of Ca2(+)-channel gating may be an important mechanism for regulating hormone secretion from pituitary cells.     

甲状腺功能对血清脂质浓度影响的初步探讨

对８５例甲状腺功能障碍病人的血清Ｔ３、ＦＴ４、ＴＳＨ、ＴＣ、ＬＤＬ－Ｃ、ＨＤＬ－Ｃ、ＡｐｏＡＩ、ＡｐｏＢ和ＬＰ（ａ）在治疗前和治疗后甲状腺素正常或接近正常值浓度时进行了测定。结果表明：甲状腺功能失调不仅影响ＴＣ、ＬＤＬ－Ｃ和ＡｐｏＢ的浓度,而且也明显影响ＬＰ（ａ）的浓度。     

Synapsin I is a spectrin-binding protein immunologically related to erythrocyte protein 4.1

The membrane-associated cytoskeleton is considered to be the apparatus by which cells regulate the properties of their plasma membranes, although recent evidence has indicated additional roles for the proteins of this structure, including an involvement in intracellular transport and exocytosis (see refs 1-3 for review). Of the membrane skeletal proteins, to date only spectrin (fodrin) and ankyrin have been purified and characterized from non-erythroid sources. Protein 4.1 in the red cell is a spectrin-binding protein that enhances the binding of spectrin to actin and can apparently bind to at least one transmembrane protein Immunoreactive forms of 4.1 have been detected in several cell types, including brain. Here we report the purification of brain 4.1 on the basis of its cross-reactivity with erythrocyte 4.1 and spectrin-binding activity. We further show that brain 4.1 is identical to the synaptic vesicle protein, synapsin I, one of the brain's major substrates for cyclic AMP and Ca2+-calmodulin-dependent kinases. Spectrin and synapsin are present in brain homogenates in an approximately 1:1 molar ratio. Although synapsin I has been implicated in synaptic transmission, no activity has been previously ascribed to it.     

Sequential interactions with Sec23 control the direction of vesicle traffic

How the directionality of vesicle traffic is achieved remains an important unanswered question in cell biology. The Sec23p/Sec24p coat complex sorts the fusion machinery (SNAREs) into vesicles as they bud from the endoplasmic reticulum (ER). Vesicle tethering to the Golgi begins when the tethering factor TRAPPI binds to Sec23p. Where the coat is released and how this event relates to membrane fusion is unknown. Here we use a yeast transport assay to demonstrate that an ER-derived vesicle retains its coat until it reaches the Golgi. A Golgi-associated kinase, Hrr25p (CK1δ orthologue), then phosphorylates the Sec23p/Sec24p complex. Coat phosphorylation and dephosphorylation are needed for vesicle fusion and budding, respectively. Additionally, we show that Sec23p interacts in a sequential manner with different binding partners, including TRAPPI and Hrr25p, to ensure the directionality of ER-Golgi traffic and prevent the back-fusion of a COPII vesicle with the ER. These events are conserved in mammalian cells.     

毛果冷杉湿心材的闭塞纹孔及细菌对木材结构的降解

扫描电镜观察到毛果冷杉湿心材部位管胞具缘纹孔纹孔膜上存在着水痕状、片状或块状的细菌,而在正常材部位没有发现。细菌的活动不但使湿心材部位的部分射线薄壁细胞发生降解,而且纹孔膜塞缘的微纤丝束也偶尔被降解而产生断裂。生材时,湿心材管胞间的具缘纹孔纹孔膜严重结壳并闭塞,早、晚材管胞具缘纹孔的闭塞率分别为77.7%和72.1%,而正常材大多数是非闭塞的,早、晚材的闭塞程度分别只有6.8%和13.4%。湿心材中存在的大量闭塞纹孔,是导致木材干燥困难的主要原因。     

Inhibin beta in central neural pathways involved in the control of oxytocin secretion

Inhibin (I) a gonadal hormone glycoprotein which suppresses follicle-stimulating hormone (FSH) secretion from the anterior pituitary, is a heterodimer consisting of an alpha subunit and one of two distinct beta subunits. S1 nuclease analysis has revealed that RNAs encoding all three subunits (alpha, beta A and beta B) are expressed in rat brain. We report here on the localization, and a potential function, of inhibin beta in the rat brain. A cell group centred in the nucleus of the solitary tract (NTS), a major recipient of visceral sensory information, was stained immunohistochemically with antisera against synthetic fragments of I beta, but not I alpha. The distribution of I beta-stained fibres is consistent with known NTS projections, and includes a prominent projection to oxytocinergic aspects of the magnocellular neurosecretory system.