泥螺生殖系统的组织学

泥螺为雌雄同体。生殖系统包括交媾器和生殖器本部。交媾器包括刺激器、阴茎和摄护腺;生殖器本部主要包括两性腺、缠卵腺和蛋白腺。刺激器和阴茎都具有非常发达的肌肉组织,腔壁游离面具纤毛。阴茎腔壁为单层柱状细胞;摄护腺被膜为一层薄的肌纤维,里面具有许多分泌细胞;缠卵腺被膜为单层扁平上皮,下层为环肌,腺体组织由分泌小管构成。蛋白腺主要由皮质层和导管层组成,皮质层内充满了分泌细胞,导管层由许多分泌小管构成,管壁为柱状腺细胞。     

四川短尾唾液腺的组织学观察

利用生物显微技术观察和研究了四川短尾鼩(Anourosorex squamipes)唾液腺的组织结构。结果表明,腮腺属纯浆液腺,有闰管和分泌管,无颗粒曲管;颌下腺属混合腺,以混合性腺泡为主,有少量浆液性腺泡和黏液性腺泡,有闰管、颗粒曲管和分泌管;舌下腺属纯黏液腺,有闰管和分泌管,无颗粒曲管,但在分泌管上存在有颗粒曲管细胞。     

捕食性蝽类唾液腺解剖方法—以叉角厉蝽为例

唾液腺的解剖是研究捕食性蝽类唾液成分及功能的关键。以叉角厉蝽Eocanthecona furcellata为例,报道了解剖获得其完整唾液腺的方法。该方法与其他解剖方法相比明显不同之处在于使用镊子固定虫体,更有利于唾液腺的解剖与收集。通过拍照观察,叉角厉蝽的唾液腺由主腺、副腺、肺门和导管组成。主腺可分为主腺前叶和主腺后叶,它们之间通过肺门相连。主腺肺门处着生有两根导管,其中一根导管与口器相连,而另一根导管与副腺连接。本文描述的解剖方法以及叉角厉蝽唾液腺形态结构可用于指导解剖获得其它捕食性蝽类的唾液腺,进而提取唾液开展成分鉴定和功能研究。     

乳腺注射法表达人组织型纤溶酶原激活剂的研究

目的 :构建tPA乳腺定位表达载体 ,使其在牛乳汁中高效表达 ,观察目的基因表达的规律及其影响因素 ,为建立新型牛乳腺生物反应器提供理论基础。方法 :RT-PCR法克隆目的基因 ,通过酶切、连接、分离、纯化等方法构建含tPA-cDNA的乳腺定位表达载体 ;采用乳腺注射法将融合基因转入小鼠及牛的乳腺组织中。结果 :乳腺注射外源基因后 ,tPA可在小鼠和牛的乳汁中表达。结论 :乳腺注射法可使目的基因在乳腺组织中稳定地表达较长的时间 ,其表达量与显微注射法没有明显的差异 ,表明外源基因的表达不受转基因方法的影响。但tPA在牛乳汁中的表达量明显高于小鼠的表达量 ,提示不同动物的乳蛋白调控系统有一定的差异 ,可能受着不同的因素或调控系统的影响。     

Alligator tears: a reevaluation of the lacrimal apparatus of the crocodilians

The Harderian gland is a poorly understood anterior ocular gland that occurs in most terrestrial vertebrates. Numerous extraorbital functions have been ascribed to the Harderian gland, principally based on its association with the nasolacrimal duct. Few studies have centered on archosaurs and the majority of those available focused solely on the Harderian gland of birds. Little is known about the lacrimal apparatus of the crocodilians. We examined the lacrimal apparatus of several specimens of Alligator mississippiensis anatomically, histologically, and histochemically and studied the embryogenesis of this system. The nasolacrimal duct possesses a distal secretory area, which is more convoluted than that of typical mammals or lepidosaurs. The alligator Harderian gland possesses a unique combination of characteristics found in lepidosaurs, birds, and mammals. Like that of both mammals and lepidosaurs, it is a large, tuboloacinar gland that appears to secrete both mucoprotein and lipids. However, the presence of blood vessels and immune cells is reminiscent of that of the avian Harderian gland. The immunogenesis of the alligator Harderian gland appears to be tied to the development of the vascular system. The presence of a distinct palpebral gland in the anterior aspect of the ventral eyelid is a feature unique to alligators. Based on position, this gland does not appear to be homologous to the anterior lacrimal gland of lepidosaurs. Lymphatic aggregations were also found in the palpebral gland. The presence of interstitial immune cells in the orbital glands of alligators suggests that the alligator lacrimal apparatus, like that of birds, may play a role in the head-associated lymphatic tissue system.     

小鼠乳腺细胞凋亡及瘦素对凋亡的影响

目的系统的研究小鼠乳腺发育周期中乳腺细胞凋亡情况,并阐明瘦素对乳腺细胞凋亡的影响。方法以小鼠乳腺为实验材料,采用TUNEL法系统地研究小鼠乳腺在青春期、妊娠期、泌乳期和退化期的整个发育周期中的细胞凋亡情况,并通过培养基中添加瘦素的方法研究瘦素对乳腺细胞凋亡的影响。结果在青春期50～60d、妊娠期10～16d、退化期1～10d检测到较多的细胞凋亡,其中退化期细胞凋亡最为显著。添加瘦素培养的乳腺细胞凋亡信号明显增多。结论小鼠乳腺发育不同时期细胞凋亡同结构和功能发育之间相互联系。同时通过小鼠乳腺组织体外培养的方法,证明瘦素在退化期乳腺组织中可明显诱导组织凋亡。     

The comparative morphology of epidermal glands in Pentatomoidea (Heteroptera)

The Heteroptera show a diversity of glands associated with the epidermis. They have multiple roles including the production of noxious scents. Here, we examine the cellular arrangement and cytoskeletal components of the scent glands of pentatomoid Heteroptera in three families, Pentatomidae (stink bugs), Tessaratomidae, and Scutelleridae (shield-backed bugs or jewel bugs). The glands are; (1) the dorsal abdominal glands, (2) the tubular glands of the composite metathoracic gland, and (3) the accessory gland component of the composite metathoracic gland. The dorsal abdominal glands are at their largest in nymphs and decrease in size in adults. The metathoracic gland is an adult-specific gland unit with a reservoir and multiple types of gland cells. The accessory gland is composed of many unicellular glands concentrated in a sinuous line across the reservoir wall. The lateral tubular gland is composed of two-cell units. The dorsal abdominal glands of nymphs are composed of three-cell units with a prominent cuticular component derived from the saccule cell sitting between the duct and receiving canal. The cuticular components that channel secretion from the microvilli of the secretory cell to the exterior differ in the three gland types. The significance of the numbers of cells comprising gland units is related to the role of cells in regenerating the cuticular components of the glands at moulting in nymphs.     

LOCALIZATION OF EXTRANEURONAL DOPAMINE-β-HYDROXYLASE IN RAT SALIVARY GLAND BY IMMUNOFLUORESCENCE HISTOCHEMISTRY

Abstract— Superior cervical ganglionectomy results in a complete noradrenergic neuronal denervation of the rat sublingual-submaxillary salivary gland. Dopamine-β-hydroxylase activity in the serous submaxillary gland falls approximately 90% after noradrenergic denervation; but in the mucinproducing sublingual gland dopamine-β-hydroxylase activity is reduced by only 33%. Dopamine-β-hydroxylase immunofluorescence in the submaxillary gland is distributed with noradrenergic neurons and is eliminated by superior cervical ganglionectomy. In the sublingual gland dopamine-β-hydroxylase immunofluorescence is localized within mucinous acini and small ducts, and the disposition and intensity of staining materials is not affected by noradrenergic denervation for up to 30 days. DBH protein in the sublingual gland had little physiologic activity in vivo. Low levels of authentic dopamine-β-hydroxylase activity were detected in saliva. Thus, dopamine-β-hydroxylase protein is present in the sublingual gland in an extraneuronal location and appears to be a secretory product of the gland.     

Mfge8 is critical for mammary gland remodeling during involution

Apoptosis is a critical process in normal mammary gland development and the rapid clearance of apoptotic cells prevents tissue injury associated with the release of intracellular antigens from dying cells. Milk fat globule-EGF-factor 8 (Mfge8) is a milk glycoprotein that is abundantly expressed in the mammary gland epithelium and has been shown to facilitate the clearance of apoptotic lymphocytes by splenic macrophages. We report that mice with disruption of Mfge8 had normal mammary gland development until involution. However, abnormal mammary gland remodeling was observed postlactation in Mfge8 mutant mice. During early involution, Mfge8 mutant mice had increased numbers of apoptotic cells within the mammary gland associated with a delay in alveolar collapse and fat cell repopulation. As involution progressed, Mfge8 mutants developed inflammation as assessed by CD45 and CD11b staining of mammary gland tissue sections. With additional pregnancies, Mfge8 mutant mice developed progressive dilatation of the mammary gland ductal network. These data demonstrate that Mfge8 regulates the clearance of apoptotic epithelial cells during mammary gland involution and that the absence of Mfge8 leads to inflammation and abnormal mammary gland remodeling.     

The chemical composition of the uropygial gland secretion of rock dove Columba livia

The uropygial gland is a holocrine secretory gland of birds. The lipid and the waxy sebum that the gland secretes is coated on the beak and transferred to the plumage in preening. The composition of the gland secretions from birds of different species has been determined, but little is known about the lipids of the secretion of the gland of the rock dove Columba livia. The amount of secretion, the total lipid content and the fatty acids composition of the secretion of C. livia captured in the nonbreeding season was reported. The mean amount of the secretion within the gland was 30 mg; the mean lipid content of the secretion was 0.385 mg/mg of secretion, which was equivalent to approximately 38% of the secretion. The weight of the secretion relative to gland weight was 32%. If we assume that the amount of the gland secretion constitutes a valid parameter to determine the degree of the gland development, our results indicate that the physiological role of the gland does not depend upon gland mass (GW); the rock dove in particular has a small gland, but its secretion represented 32% of the gland's mass. The composition of the lipids extracted from the gland secretion consisted of C14 to C20 fatty acids, most of them were unsaturated. The secretion of the gland contained approximately 59% of unsaturated fatty acids with a prevalence of oleic acid (37%) and a low content of linoleic (6%) and arachidonic acids (7%). The saturated long chain fatty acids were mainly 14:0, 16:0 and 18:0 in a percentage of approximately 34%. No sexual differences were found in any of the evaluated parameters.     

Uterine gland formation in mice is a continuous process, requiring the ovary after puberty, but not after parturition

Uterine gland formation occurs postnatally in an ovary- and steroid-independent manner in many species, including humans. Uterine glands secrete substances that are essential for embryo survival. Disruption of gland development during the postnatal period prevents gland formation, resulting in infertility. Interestingly, stabilization of beta-catenin (CTNNB1) in the uterine stroma causes a delay in gland formation rather than a complete absence of uterine glands. Thus, to determine if a critical postnatal window for gland development exists in mice, we tested the effects of extending the endocrine environment of pregnancy on uterine gland formation by treating neonatal mice with estradiol, progesterone, or oil for 5 days. One uterine horn was removed before puberty, and the other was collected at maturity. Some mice were also ovariectomized before puberty. The hormone-treated mice exhibited a delay in uterine gland formation. Hormone-treatment increased the abundance of uterine CTNNB1 and estrogen receptor alpha (ESR1) before puberty, indicating possible mechanisms for delayed gland formation. Despite having fewer glands, progesterone-treated mice were fertile, suggesting that a threshold number of glands is required for pregnancy. Mice that were ovariectomized before puberty did not undergo further uterine growth or gland development. Finally, to establish the role of the ovary in postpartum uterine gland regeneration, mice were either ovariectomized or given a sham surgery after parturition, and uteri were evaluated 1 wk later. We found that the ovary is not required for uterine growth or gland development following parturition. Thus, uterine gland development occurs continuously in mice and requires the ovary after puberty, but not after parturition.     

Survey of the exocrine system in Protanilla wallacei (Hymenoptera,Formicidae)

We studied the exocrine system of both workers and ergatoid queens of Protanilla wallacei using light, scanning and transmission electron microscopy. Our survey revealed the presence of 26 glands, of which 6 had never been found before in ants. Five of these represent novel discoveries for social insects in general. The overall novel discoveries comprise an epithelial stipes gland, a pharyngeal wall gland, a central petiole gland, a lateral postpetiole gland and a foot-sole gland in the hindleg pretarsi. The intramandibular epithelial gland was already reported in some bees previously, but is now for the first time also reported in ants. The exocrine system of workers and ergatoid queens is very similar, with only the spermathecal gland showing an obvious difference. This is in line with the limited anatomical as well as behavioural difference between both castes in Protanilla compared to the situation in Leptanilla.     

MiR-486 Regulates Lactation and Targets the PTEN Gene in Cow Mammary Glands

Mammary gland development is controlled by several genes. Although miRNAs have been implicated in mammary gland function, the mechanism by which miR-486 regulates mammary gland development and lactation remains unclear. We investigated miR-486 expression in cow mammary gland using qRT-PCR and ISH and show that miR-486 expression was higher during the high-quality lactation period. We found that miR-486 targets phosphoinositide signaling in the cow mammary gland by directly downregulating PTEN gene expression and by altering the expression of downstream genes that are important for the function of the mammary gland, such as AKT, mTOR. We analyzed the effect of β-casein, lactose and triglyceride secretion in bovine mammary gland epithelial cells (BMECs) transfected by an inhibitor and by mimics of miR-486. Our results identify miR-486 as a downstream regulator of PTEN that is required for the development of the cow mammary gland.     

Cloning and characterization of a candidate nutritive glycoprotein from the albumen gland of the freshwater snail, Helisoma duryi (Mollusca: Pulmonata)

Abstract. The albumen gland is a female accessory sex gland that synthesizes and secretes perivitelline fluid around pulmonate eggs. The perivitelline fluid is composed of mainly galactogen and proteins, and is thought to provide nourishment to the embryos during development. We have previously identified the major secretory protein of the albumen gland of the freshwater snail Helisoma duryi as a native glycoprotein of ∼288 kDa, consisting of four 66-kDa subunits. In this study, the major albumen gland protein in H. duryi was purified, cloned, and the full-length cDNA sequence determined. Nucleotide sequence analysis revealed that the albumen gland protein (HdAGP) shared 83% identity with a partial cDNA sequence from a developmentally regulated albumen gland protein in Biomphalaria glabrata . The HdAGP mRNA was detected by RT-PCR in the albumen gland, ovotestis, mantle and digestive gland. SDS-PAGE analysis of the albumen gland protein in egg masses at different stages of development showed that the amount of HdAGP steadily decreased during embryogenesis, suggesting its possible catabolism by the developing embryos. Protein domain searches suggested that the HdAGP shared limited sequence identity, and adopted a similar three-dimensional conformation to the bactericidal, permeability increasing, protein family, raising the possibility of a potential bactericidal function for this important reproductive/developmental protein.     

Distribution and comparative morphology of the cloacal gland in ants (Hymenoptera : Formicidae)

The cloacal gland is a paired exocrine structure, which has so far been described only in the formicine species, Camponotus ephippium and Cataglyphis savignyi (Hymenoptera : Formicidae). The gland is formed by 2 clusters of bicellular units with slender duct cells, releasing the glandular secretion through the cloacal membrane. In the present work, a number of ant species, largely of the Formicinae subfamily, have been surveyed for the presence of a cloacal gland. The gland is present in nearly all formicines screened, albeit with a variable development. Cataglyphis, one of the genera with a very prominent cloacal gland, was chosen for a more detailed comparative study. At the ultrastructural level, secretory cells were observed having a well-developed smooth endoplasmic reticulum and Golgi apparatus, typical for pheromone-producing glandular cells. The gland is also present in all dolichoderines screened, but in none of the species of the Aneuretinae, Myrmeciinae, Myrmicinae, Nothomyrmeciinae, or Pseudomyrmecinae investigated. This provides tentative evidence that the cloacal gland is a synapomorphy of the Formicinae and Dolichoderinae, giving support for their hypothesized sister group relationship. Up to now, the function of the cloacal gland remains largely enigmatic.     

Putrescine, a source of gamma-aminobutyric acid in the adrenal gland of the rat.

Putrescine is the major source of gamma-aminobutyric acid (GABA) in the rat adrenal gland. Diamine oxidase, and not monoamine oxidase, is essential for GABA formation from putrescine in the adrenal gland. Aminoguanidine, a diamine oxidase inhibitor, decreases the GABA concentration in the adrenal gland by more than 70% after 4 h, and almost to zero in 24 h. Studies using [14C]putrescine confirm that [14C]GABA is the major metabolite of putrescine in the adrenal gland. Inhibition of GABA transaminase by amino-oxyacetic acid does not change the GABA concentration in the adrenal gland, as compared with the brain, where the GABA concentration rises. With aminoguanidine, the turnover time of GABA originating from putrescine in the adrenal gland is 5.6 h, reflecting a slower rate of GABA metabolism compared with the brain. Since GABA in the adrenal gland is almost exclusively derived from putrescine, the role of GABA may relate to the role of putrescine as a growth factor and regulator of cell metabolism.     

In vivo evidence for epidermal growth factor receptor (EGFR)-mediated release of prolactin from the pituitary gland

Members of the epidermal growth factor receptor (EGFR/ERBB) system are essential local regulators of mammary gland development and function. Emerging evidence suggests that EGFR signaling may also influence mammary gland activity indirectly by promoting the release of prolactin from the pituitary gland in a MAPK and estrogen receptor-α (ERα)-dependent manner. Here, we report that overexpression of the EGFR ligand betacellulin (BTC) causes a lactating-like phenotype in the mammary gland of virgin female mice including the major hallmarks of lactogenesis. BTC transgenic (BTC-tg) females showed reduced levels of prolactin in the pituitary gland and increased levels of the hormone in the circulation. Furthermore, treatment of BTC-tg females with bromocriptine, an inhibitor of prolactin secretion, blocked the development of the lactation-like phenotype, suggesting that it is caused by central release of prolactin rather than by local actions of BTC in the mammary gland. Introduction of the antimorphic Egfr allele Wa5 also blocked the appearance of the mammary gland alterations, revealing that the phenotype is EGFR-dependent. We detected an increase in MAPK activity, but unchanged phosphorylation of ERα in the pituitary gland of BTC-tg females as compared with control mice. These results provide the first functional evidence in vivo for a role of the EGFR system in regulating mammary gland activity by modulating prolactin release from the pituitary gland.     

Histological and histochemical observations on the foot glands in some byssus-bearing bivalves of the Waltair coast

Summary The glands responsible for the formation of the byssus threads inArca symmetrica, Barbatia obliquata andSeptifer bilocularis are the white gland, phenol gland and enzyme gland. Besides these, mucous glands are also present in the sub-epithelia. The size and shape of the cells of these glands vary in one and the same species. From histochemical investigations it has been revealed that these glands contain 1,2-glycol groups in addition to disulphides and sulphhydryls. The white gland secretes a protein material and the phenol gland is rich in phenols. These two combine to form a phenolic protein which is acted upon by a polyphenol oxidase secreted by the enzyme gland and leads to the formation of a byssus thread. The mucous gland cells secrete acid mucopolysaccharides, neutral mucins and glycoproteins.     

脉红螺消化系统的形态学研究

脉红螺消化系统由十二个器官组成。其消化管壁都由粘膜层、粘膜下层、肌层和外膜四层结构构成。作者对消化腺的细胞进行了较详细的描述,并利用组化方法测定消化腺细胞中含有的酶类。作者还对部分器官的超微结构进行了观察。     

乳腺重构的过程及其调节因素

受到妊娠周期的影响，乳腺组织在雌性哺乳动物一生中经历着妊娠-哺乳-退化的周期性发育变化. 在乳腺退化到再次泌乳的过程中，乳腺细胞经历凋亡和更新，从而实现乳腺组织的自我更新和修复，即乳腺重构. 重构期间乳腺在组织结构和生理过程中发生显著变化，但该过程物种间差异较大. 乳用家畜为维持泌乳，妊娠期和干奶期重叠，展示出独特的再生性乳腺重构. 再生性乳腺重构对乳畜乳腺健康和下一周期的泌乳具有重要意义，研究此过程将为后续调控乳腺自我更新和改善乳腺健康提供思路. 本综述总结了近年来动物乳腺重构的研究进展，系统归纳了影响乳腺重构的因素，包括激素、蛋白酶、细胞因子、热应激、氧化应激、光照周期等，旨在解析乳腺重构的生理机制，为精准调控该过程提供科学依据.