The uterovaginal sperm host glands of the quail (Coturnix coturnix japonica)

Summary Ultrastructural and ultrahistochemical studies were performed on the uterovaginal sperm host glands of the quail (Coturnix coturnix japonica). The proximal parts of the glandular necks are lined by a pseudostratified epithelium, consisting of high columnar ciliated cells and small, irregular shaped, basal cells.The true glandular epithelium is composed only of columnar cells with microvilli on their luminal end. A characteristic luminal feature is a large lipid droplet in the perinuclear region. In the subplasmalemmal region numerous tubular profiles are seen which could represent a cellular resorption system.To evaluate the absorptive capacity of the Uterovaginal sperm host glands, tracer studies with HRP, ferritin, lanthanum and ruthenium red were undertaken. Since between 5 min and 3 h after injection no absorption could be found with the techniques mentioned, it is suggested that phagocytosis of spermatozoa by the glandular epithelium is not likely to occur.     

Fine structural organization of a non-reticulate plant cell nucleus

We studied the fine structural organization of the meristematic nucleus in roots of Lycopesicon esculentum (tomato) using ultracytochemical and immunocytochemical approaches. The nucleus has a non-reticulate (i.e. low DNA content) structure whose supramolecular organization differs in some respects from that in reticulate nuclei, principally in the organization of the chromocentres associated with the nuclear envelope, with which centromeric structures appear to be associated. The main difference at the nucleolar level is found in the fibrillar centres, which have a low amount of DNA labelling and in which inclusions of condensed chromatin are present only very rarely. The distribution of nucleolar DNA amongst the nucleolar compartments is similar to that in reticulate nucleoli as demonstrated using an anti-DNA monoclonal antibody. Tomato nuclei have nucleolus-associated bodies or karyosomes, like other plant species with a low DNA content and non-reticulate nuclear organization. The nuclear ribonucleoprotein structures in the inter- and perichromatin regions, namely inter- and perichromatin fibrils and granules, show similar ultrastructural and cytochemical characteristics in both types of nuclei.Abbreviations NAC nucleolus associated chromatin - CES centromeric structures - NOR nucleolar organizing region - NAB nucleolus associated body - IG interchromatin granules - RNP ribonucleoprotein - Mab monoclonal antibody by M.F. Trendelenburg     

Localization of adenylate cyclase activity in the tissues of an intact planarian Dugesia lugubris (O. Schmidt)

Summary Adenylate cyclase was localized in tissues of an intact planarian Dugesia lugubris (O. Schmidt) by ultracytochemical methods. The enzyme was found in epithelium, muscles, secretory cells (mucous), and rhabdites forming cells and neoblasts. Adenylate cyclase occurred on the external side of cell membranes in cisterns of the endoplasmic reticulum, nuclear envelope and mitochondria. The problems of ultracytochemical localization of AC are discussed.     

In vivo production of the nucleolar channel system in post menopausal endometrium

Summary Endometrial biopsies from seven postmenopausal women on hormone replacement therapy have been examined for the presence of the unique nuclear structure, the nucleolar channel system. Its identification in five of the patients has demonstrated that the nucleolar channel system can be produced by an appropriate oestrogen and progestagen treatment and is not otherwise dependent on ovulation.     

Ultrastructural and ultracytochemical study of the middle ear epithelium in the chicken,Gallus gallus domesticus

The fine structure of the epithelium lining the tympanic cavity of the chicken was studied by TEM and SEM. In addition, the distribution of nonspecific esterase activity in the epithelium was investigated by TEM. Ultrastructural study revealed the presence of disk-like apical protrusions of the epithelial cells, previously not observed in other cell types. The protrusions contained some cytoplasmic organelles and were characterized by a ring-shaped thickening around their periphery. The ring was made up of a granulo-filamentous material. Our observations clearly indicate the existence of an apocrine secretory mechanism, consisting of a progressive detachment of disk-like protrusions from the apex of the epithelial cells. The ultracytochemical study demonstrated nonspecific esterase activity on the epithelial surface and in the secretory vesicles. We propose that nonspecific esterase is a marker for middle ear surfactant in birds.     

Ultrastructural differentiation of glandular stomach (proventriculus) in chick embryo

Cytochemical characterization of mucosubstances of chick glanular stomach (proventriculus) changes from 15 days of development to postnatal and adult stages was studied. To corroborate these data cytochemical, ultrastructural and ultracytochemical study of chick embryo proventriculus from 7 to 20 days of development was performed. At the 7th day several layers of undifferentiated cells formed an epithelium which covered the walls of the glandular stomach. Mocosubstances were not found. Between the 9th and 5th day a single layer of cylindrical cells was encountered forming invaginations which originated deep glands. Three types of cells were separated from the above mentioned layer, dark, clear and undifferentiated. The dark cells had organelles which are involved in protein synthesis and the clear ones were rich in mitochondria. Argentaffine cells appeared at 15th day instead mucosubstances formed a thin coat on the epithelium at 9th day which increased at the end of development in the apical cytoplasm and gland cells. These observations demonstrate that proventriculus of chick embryo has ultrastructurally differentiated cells involved with enzymatic and hydrochloric acid secretion after the 9th day. These progressive events are correlated with the digestion process of yolk during embryogenesis. At the end of development the proventriculus has completely organized the glandular layer.     

Ultracytochemistry of cyclic 3',5'-nucleotide phosphodiesterase activity in the planarian Dugesia lugubris (O. Schmidt)

The enzyme 3',5'-nucleotide phosphodiesterase was localized in certain tissues of the planarian Dugesia lugubris (O. Schmidt) by means of ultracytochemical methods. This enzyme was found to be active in epithelium, muscles, nerve tissue and in rhabdite-forming cells. The active enzyme was present at the outer or inner side of the membrane, and even in the cytoplasm. Problems of the ultracytochemical localization of PDE are discussed.     

Estradiol receptor binding to the epithelium of uterine lumen and glands: region- and time-related changes during preimplantation and periimplantation periods studied by autoradiography

The presence and changes of estradiol nuclear binding and related functions in uterine luminal and glandular epithelium were studied before and after blastocyst implantation using receptor autoradiography with ³H-estradiol-17 in association with ³H-thymidine incorporation and immunocytochemical binding of antibody to estrogen receptor ER-. ³H-estradiol nuclear binding is present but variable during days 1.5–7.5 of pregnancy. Sites of strong nuclear binding of ³H-estradiol exhibit strong immunocytochemical staining with ER- antibody. Qualitative and quantitative evaluation of autoradiograms reveal that there is a general increase of nuclear ³H-estradiol binding during the first 3 days after fertilization in both luminal and glandular epithelium. The binding of estradiol is stronger in glandular epithelium from day 2.5 to day 7.5, paralleled by a rise in ³H-thymidine incorporation on day 2.5. By comparison, in the epithelium of the uterine lumen ³H-estradiol nuclear binding is low, but relatively high in epithelial cells at lateral branching of the lumen where the increase in ³H-estradiol binding corresponds to an increased labeling index with ³H-thymidine. A highly differentiated binding of ³H-estradiol to luminal and glandular epithelium was demonstrated with region- and time-specific changes of related effects on cell proliferation, differentiation, and secretion, probably involving involution and remodeling. The strong ³H-estradiol binding to glandular epithelium suggests that estradiol exerts pronounced effects on glandular activities in the periimplantation period.     

Ultrastructural aspects of infertility.

Organ culture studies have demonstrated that 17beta oestradiol can cause the rapid deterioration and dissolution of pre-existing nuclear channel systems in the human endometrial glandular cell. The importance of the nuclear channel system in implantation is emphasized and the implications of secretory activity in the endometrium of an infertile woman are discussed.     

Early glycogenesis in the uterine glandular cells of the rabbit induced by progestins: a quantitative investigation

A single administration of progesterone (P) to primed immature rabbits induces the appearance of glycogen in uterine glandular cells. This phenomenon, which is rapid and transitory, precedes a mitotic surge in the glandular epithelium. Ultrastructural studies allowed us to observe the beginning of glycogenesis as early as 1 h after the injection of P. Quantitative image analysis in the course of a kinetic study showed that glycogen levels reached a maximum at the sixth h and after 24 h had fallen dramatically. Promegestone, a potent progestomimetic compound, gave similar results, but estradiol, testosterone and dexamethasone failed to induce the appearance of glycogen in the uterine glands. Mifepristone (RU 486) had an antagonistic effect on the action of P. These results suggest that early P-dependent glycogenesis in the endometrial glandular cells of the rabbit may play an important role in the increased rate of mitosis and cellular proliferation that are necessary events in preparing the endometrium for implantation.     

Ultrastructural modifications of renal cells in the three-spined stickleback (Gasterosteus aculeatus L.) after castration

Summary The mechanisms of cellular autophagy have been studied in the renal epithelium of male sticklebacks (Gasterosteus aculeatus L.) following castration. Two main types of alteration are described at the level of the proximal tubule cells. At first, the formation of endoplasmic reticulum whorls is observed, followed immediately by the secretion of lacunar progranules and by nucleolar modifications. These alterations lead to a progressive decrease of the glandular activity of the cells. The other main effect of castration is a general involution of the secretory granules still present in the cells. The involutive processes which lead to the complete destruction of the secretory material and, sometimes, of entire proximal cells, are described.In the collecting tubules, a marked and rapid decrease in glandular activity occurs, followed by disappearance of the mucous secretions. Small dense granules, supposedly lysosomes, are present.The processes described also appear to be characteristic of the normal involution of the renal cells occurring at the end of the breeding period. The findings strongly suggest that the male sex hormone may exert a double control on the renal cells in the stickleback, at both the cytoplasmic and nucleolar levels.I am greatly indebted to Prof. E. Follénius, who contributed to this work with innumerable suggestions and valuable advice. I also wish to thank Mr. C. Chevalier and Miss A. Meunier for their technical collaboration     

Ultrastructural cytochemistry of the nucleus and nucleolus in growing rabbit oocytes

Summary— Ultrastructural changes of the germinal vesicle during the growth of rabbit oocytes were studied by means of light and electron microscopy, ³H-uridine autoradiography, Ag-NOR staining and E-PTA staining. Particular interest was paid to the nucleologenesis and condensation of chromatin. In contrast to other mammalian species, chromosome condensation in rabbit oocytes occurred concomitantly with rRNA synthesis-dependent nucleolar compaction and preceded nuclear envelope breakdown and resumption of meiosis.     

The effect of temperature and ageing on root apical meristems during seedling growth of Triticum aestivum L.: a specific effect on nucleoli

Abstract. Growth and cytology of root apical meristems of Chinese Spring wheat were studied in relation to temperature. The maximum rate of growth increased with temperature, a marked rise occurring between 10°C and 12°C. At all temperatures studied nucleolar volume increased to a maximum and then declined. The maximum nucleolar size achieved showed particular temperature sensitivity, higher volumes being attained at lower temperatures. The peak at 5°C was 70% higher than at 20°C. However, in comparison, cell and nuclear volumes were only 38% and 47% larger, respectively. Ultrastructural analysis of the nucleoli revealed a temperature-dependent relationship between the proportion of granular component and dense fibrillar component. The results are discussed in relation to the regulation of ribosome synthesis and function during growth and development at different temperatures.     

Increased functional load on mouse kidney proximal tubule epithelial cells causes changes in nucleolar 3-D architecture

Ultrastructural 3-D analysis of nucleolar architecture and Ag-NOR protein distribution in mouse kidney-cortex proximal-tubule epithelium has been performed. A principal scheme of structural changes of the nucleolus and organization of its components during the intensification of pre-rRNA synthesis (dynamic model of a nucleolus) based on computer spatial modelling has been advanced. According to the nucleolar composition, three groups of cells, which differ from each other by rRNA synthesis, are defined in normal kidney. Most nephron proximal-section cells (about 52%) are characterized by lower activity of RNA synthesis. Such kind of cells are defined as group I (nucleolar diameter 0.7–1.5 µm) and always contain resting, ring-shaped or close to ring-shaped dense nucleoli, which have 2 or 3 fibrillar centers. Nucleoli of group II cells (about 37%, nucleolar diameter 1.5–2.5 µm) have a higher level of activity, contain 4–7 fibrillar centers, and their structural organization is close to reticulated forms due to the first indications of vacuolar network (identified as prereticulated nucleoli). The most active cells of group III (about 11%, nucleolar diameter 2.5–3.5 µm) include cells with typical reticulated nucleoli with a well expressed vacuolar network and numerous fibrillar centers (18–22). Increased functional load of the epithelium caused by unilateral nephrectomy and diuretic (4-chlor-H [2-furylmethyl] 5-sulphamyl-antranic acid) injection changed the proportion of the different cell groups: group I decreased (about 25%), whereas groups II and III increased (about 8% and 17%, respectively). The increase of nucleolar activity first causes a deformation of the individual fibrillar centers as well as complication and growth of their surface. Further, a progressive fragmentation of the fibrillar centers and the growth of their total volume is observed. The complication and growth of the total volume of Ag-positive zones is another indication of the nucleolar activation. The vacuolar system develops by a gradual fusion of small isolated cavities into a united vacuolar network. Nucleoli with 2–7 fibrillar centers are considered to be intermediate forms reflecting successive stages of its activation or inactivation: from the resting ring-shaped nucleolus via transient stages of increasing functional activity to the active reticulated nucleoli and vice versa. The observed differences in the nucleolar ultrastructure are regarded as evidence of the functional heterogeneity of cell populations within one functional segment of nephron.     

Fine structure of the female sex pheromone-producing glands in Sesamia nonagrioides lef. (Lepidoptera : Noctuidae)

The morphology and cytology of the female sex pheromone-producing glands of Sesamia nonagrioides (Lepidoptera : Noctuidae) consist of modified intersegmental membranes; they are unusual compared with those described in other moths. There are 2 different glandular areas (a ventral area, GI, around the ostium bursae and a ring-shaped area, GII, around the ovipositor), instead of a single area (between segments 8 and 9 + 10) as in most other species. Ultrastructural features, such as developed basal invaginations and dilated intercellular spaces indicate transport of material from the hemolymph to the glandular cells, while the presence of abundant mitochondria, numerous free ribosomes, rough endoplasmic reticulum, and inclusions reveal high cellular activity. The smooth endoplasmic reticulum is absent in S. nonagrioides, in contrast to its extensive development in glands producing similar compounds in other moths. The cuticle, abnormally thick (7–8 times thicker than the glandular epithelium), is traversed by dilated pore canals forming cuticular gaps, connected with epicuticular canals. This system allows the storage and the passage of pheromone in and through the cuticle.     

Distribution of progestin-binding cells in estrogen-treated and untreated neonatal mouse uterus and oviduct: autoradiographic study with [125I]progestin

Summary Progestin-binding sites in uteri and oviducts of estrogen-treated and untreated 8-day-old mice were studied by thaw-mount autoradiography with [¹²⁵I]progestin. In the untreated uteri, nuclear concentration of radiolabelled progestin was observed in all tissues of the uterus, with strongest nuclear labelling in luminal and glandular epithelia and in stroma. In the estrogen-treated uteri, the degree of labelling was markedly augmented in stroma and muscle, but much reduced in the luminal and glandular epithelia, compared to untreated uteri. In untreated oviducts, nuclear labelling was observed in stroma and muscle in all regions and in epithelium in the isthmic and uterine regions. The epithelium in infundibular and ampullar regions was only scarcely labelled. The estrogen-treatment augmented the labelling in stroma and muscle of the oviduct as in the uterus, but the labelling in epithelium was not affected. These results indicate that estrogen-treatment induces progesteron receptor differentially among tissue compartments both in the uterus and oviduct.     

Distribution of progestin-binding cells in estrogen-treated and untreated neonatal mouse uterus and oviduct: autoradiographic study with [125I]progestin

Progestin-binding sites in uteri and oviducts of estrogen-treated and untreated 8-day-old mice were studied by thaw-mount autoradiography with [125I]progestin. In the untreated uteri, nuclear concentration of radiolabelled progestin was observed in all tissues of the uterus, with strongest nuclear labelling in luminal and glandular epithelia and in stroma. In the estrogen-treated uteri, the degree of labelling was markedly augmented in stroma and muscle, but much reduced in the luminal and glandular epithelia, compared to untreated uteri. In untreated oviducts, nuclear labelling was observed in stroma and muscle in all regions and in epithelium in the isthmic and uterine regions. The epithelium in infundibular and ampullar regions was only scarcely labelled. The estrogen-treatment augmented the labelling in stroma and muscle of the oviduct as in the uterus, but the labelling in epithelium was not affected. These results indicate that estrogen-treatment induces progesterone receptor differentially among tissue compartments both in the uterus and oviduct.     

Differential expression of Toll-like receptor 4 (TLR4) in healthy and infected canine endometrium

This study provides the first report into immunohistochemical localization of Toll-like receptor (TLR) in the canine reproductive tract. TLR4 was investigated in endometrium during the estrous cycle and in pyometra. Pyometra is the most important pathological condition of the uterus due to bacterial infection in dogs. To protect against invading pathogens, the female reproductive tract has evolved immune mechanisms. TLRs are the cellular components of the afferent arm of the innate immune system. The expression of TLR4 was significantly higher in the endometrial stroma compared to the endometrial surface epithelium and glandular epithelium in proestrus. The glandular epithelium and stroma at the diestrous stage expressed TLR4 significantly higher than surface epithelium. Furthermore, when compared to other healthy groups, the glandular epithelium at diestrus also higher expressed TLR4 than other stages. The expression of TLR4 in the surface epithelium was higher in dogs with pyometra compared with all other groups. And, the surface epithelium of dogs suffering from pyometra also expressed TLR4 more intensely than the glandular epithelium. The innate immunity of infected canine endometrium response to bacterial infection is intensely extremely increased by the expression of TLR4. Furthermore, the different levels of TLR4 expression seems related to physiological changes in distinct cell types of endometrium, leukocytes populations, cytokines and sex hormones.