Morphology and histology of the endocrine glands of Zootermopsis angusticollis Hagen (Isoptera)

1972 ◽  
Vol 50 (12) ◽  
pp. 1537-1547 ◽  
Author(s):  
Cedric Gillott ◽  
Chih-Ming Yin
Keyword(s):  
Cell Types ◽  
Cell Number ◽  
Neurosecretory Cells ◽  
Corpora Allata ◽  
Endocrine Glands ◽  
Histological Changes ◽  
Secretory Cycle ◽  
Zootermopsis Angusticollis ◽  
Primary Reproductives ◽  
Median Neurosecretory Cells

The morphology and histology of the endocrine glands of the various castes of Zootermopsis angmticollis were examined. Six types of median neurosecretory cells are distinguishable by size and stain affinity. No differences in the relative numbers of these cell types among castes can be seen. It is postulated that they may be different forms of the same cell during its synthetic and secretory cycle. Lateral neurosecretory cells can be identified consistently only in mature primary reproductives of both sexes. In the corpora cardiaca two types of cells occur; the fuchsinophilic cells are distributed generally whereas the cells that take up counterstain are restricted to the center of the gland. Intercellular neurosecretory cell product is found throughout the gland. No histological changes associated with the formation of particular castes were observed. The corpora allata (CA) vary in size and histological appearance according to caste but not sex. The CA of reproductives (primary and supplementary) and presoldiers are larger than those of juveniles of the same instar; those of soldiers are about the same size as those of the corresponding juvenile stage. These size increases are due mainly to changes in the ratio cytoplasmic diameter: nuclear diameter of the constituent cells and not to an increase in cell number. The H-shaped molt glands, which, as in other pterygote insects, disappear within a few days of the imaginal molt, are composed of a large prothoracic portion and a smaller cephalic ('ventral gland') portion extending anteriorly and dorsally. Histologically the two components are indistinguishable. Running through the glands are thin strands of muscle.

Endocrine activity during caste differentiation in Zootermopsis angusticollis Hagen (Isoptera): a morphometric and autoradiographic study

1975 ◽  
Vol 53 (11) ◽  
pp. 1690-1700 ◽  
Author(s):  
Chih-Ming Yin ◽  
Cedric Gillott
Keyword(s):  
Autoradiographic Study ◽  
Neurosecretory Cells ◽  
Caste Differentiation ◽  
Corpora Allata ◽  
Synthetic Activity ◽  
Cell Diameter ◽  
Endocrine Control ◽  
Endocrine Activity ◽  
Zootermopsis Angusticollis ◽  
Primary Reproductives

The diameters of the median neurosecretory cells (MNC) and their nuclei, and the volumes of the corpora cardiaca (CC) and corpora allata (CA) were measured in termites (Zootermopsis angusticollis) of differing age, sex, and caste. The synthetic activities of the MNC and CA were estimated autoradiographically.No significant differences in the diameters of the MNC and their nuclei were observed between insects of differing age, sex, and caste, with the exception of primary reproductives whose MNC are significantly larger than those of larvae of the same instar. The six types of MNC distinguishable histologically differ in their nuclear diameter : cell diameter ratios and in their rates of [3H]uridine and [3H]cystine incorporation.The volumes and (or) synthetic activities of the CA change markedly during the differentiation of reproductives and soldiers. The CA of recently molted primary and supplementary reproductives are several times larger than those of larvae and nymphs of the previous instar, yet their synthetic activity remains low. In contrast, the CA of presoldiers and soldiers are only slightly larger than those of previous instar larvae, but show high synthetic activity. The data are discussed in terms of the endocrine control of caste differentiation.

Histological changes in the ovary in relation to yolk deposition, allatectomy, and destruction of the median neurosecretory cells in Melanoplus sanguinipes

1976 ◽  
Vol 54 (2) ◽  
pp. 185-192 ◽  
Author(s):  
R. H. Elliott ◽  
C. Gillott
Keyword(s):  
Brush Border ◽  
Follicle Cell ◽  
Neurosecretory Cells ◽  
Corpora Allata ◽  
Follicle Cells ◽  
Follicular Epithelium ◽  
Uptake Mechanism ◽  
Histological Changes ◽  
Pinocytotic Vesicles ◽  
Median Neurosecretory Cells

Histological changes in the ovary during periods of yolk deposition suggest that differentiation of the follicular epithelium and oolemma is an essential prerequisite to the pinocytotic uptake of protein into the oocytes. Before vitellogenesis, intercellular spaces form between adjacent follicle cells, and a brush border appears along the oocyte surface. The presence of protein within these spaces and of elementary yolk spheres along the brush border suggests that protein reaches the oocyte by an intercellular route.Accumulation of yolk does not occur after allatectomy or median neurosecretory cell (mNSC) cautery. Allatectomy inhibits the differentiation of the follicle cells and oolemma. In contrast, after mNSC cautery, differentiation occurs but the pinocytotic vesicles pinched off from the oolemma are empty, indicating that the availability of yolk precursors, not the uptake mechanism, has been affected. In addition, the appearance of secretion in the lateral oviducts is prevented by allatectomy, but merely delayed by mNSC cautery. The findings indicate that the corpora allata, but not the mNSC, are the source of a gonadotropin that regulates follicle-cell differentiation and the development of secretion in the lateral oviducts.

Changes in cell number and activity of the corpora allata of the cockroach Diploptera punctata: a role for mating and the ovary

1984 ◽  
Vol 62 (11) ◽  
pp. 2178-2182 ◽  
Author(s):  
S. S. Tobe ◽  
N. Clarke ◽  
B. Stay ◽  
R. P. Ruegg
Keyword(s):  
Juvenile Hormone ◽  
Cell Number ◽  
Neurosecretory Cells ◽  
Corpora Allata ◽  
Surgical Removal ◽  
Gonotrophic Cycle ◽  
Biosynthetic Activity ◽  
Diploptera Punctata ◽  
Number Of Cells ◽  
Mated Female

The corpora allata (CA) of mated female Diploptera punctata showed an increase in cell number from 6000 cells/CA on the day of emergence to a maximum of about 9000 cells/CA by day 5. The number of cells per CA then declined and, by day 8, the CA was composed of about 6000 cells. In the normal mated animal, the previously established increase in biosynthetic activity of the CA correlated with the increase in number of cells in the CA. In virgin females no significant change in cell number was observed during this period and this correlates with the demonstrated low and constant rates of juvenile hormone (JH) biosynthesis. Following ovariectomy, however, an increase in cell number occurred (to 10 000 cells/CA) by day 5 and cell number remained elevated until at least day 8. Low rates of JH biosynthesis have been observed previously in ovariectomized females and thus the increase in cell number observed in these females is not accompanied by a corresponding increase in biosynthetic activity. The cell number of the CA in ovariectomized females was reduced by injection of 20-hydroxyecdysone. We propose that either mating or surgical removal of inhibitory signals from cerebral neurosecretory cells permits the proliferation of the cells of the CA. We also propose that factors from the ovary are responsible for both the initiation of the cycle of JH biosynthesis and the reduction of CA cell number at the end of the gonotrophic cycle.

Changes in the protein concentration and volume of the haemolymph in relation to yolk deposition, ovariectomy, allatectomy, and cautery of the median neurosecretory cells in Melanoplus sanguinipes

1977 ◽  
Vol 55 (1) ◽  
pp. 97-103 ◽  
Author(s):  
R. H. Elliott ◽  
C. Gillott
Keyword(s):  
Protein Synthesis ◽  
Total Protein ◽  
Protein Concentration ◽  
Neurosecretory Cells ◽  
Corpora Allata ◽  
Total Protein Content ◽  
Concentration Increase ◽  
Protein Levels ◽  
Low Protein ◽  
Median Neurosecretory Cells

The protein concentration and volume of the haemolymph may change with no apparent relation to one another in normal, ovariectomized, allatectomized, and median-neurosecretorycell-cauterized (mNSC-cauterized) females. Therefore, protein levels in the haemolymph are more meaningfully expressed in terms of the total protein content. In normal females, fluctuations in the haemolymph volume tend to parallel changes in the protein concentration during the first and subsequent gonotrophic periods. However, significantly less protein accumulates during the latter periods. The suggestion that these fluctuations partly reflect changes in the vitellogenic requirements of the oocytes is supported by the finding that both the volume and protein concentration increase significantly after ovariectomy.Allatectomy or mNSC cautery prevents the normal accumulation of protein in the haemolymph. In allatectomized females, the slight increase in protein concentration is accompanied by a decline in haemolymph volume. Cautery of the mNSC, provided it is performed within 3 h of emergence, results in a low protein concentration but has no effect on the haemolymph volume. The observations are discussed in terms of the corpora allata and mNSC control of haemolymph protein synthesis.

Age-related histological changes in neurosecretory cells in the supraoesophageal ganglion of Nereis virens (Annelida, Polychaeta)

1980 ◽  
Vol 58 (10) ◽  
pp. 1735-1740 ◽  
Author(s):  
Kathryn Bell ◽  
Joan R. Marsden
Keyword(s):  
Light Microscopy ◽  
Developmental Stages ◽  
Cell Types ◽  
Staining Intensity ◽  
Neurosecretory Cells ◽  
Histological Changes ◽  
Nereis Virens ◽  
Age Related ◽  
P Cells ◽  
The Brain

The supraoesophageal ganglion of Nereis virens has been surveyed by light microscopy to determine the locations of probable neurosecretory cells. Neurons reacting with paraldehyde fuchsin are found scattered throughout the brain, but the majority are accumulated posteriorly in nucleus 20. This nucleus was examined in some detail, and the histology of four cell types is described. Two types (p and r) are strongly paraldehyde-fuchsin-positive, and may be secretory. On the basis of other staining characteristics, and uptake of labelled cystine, it is concluded that p cells are rich in cystine and (or) cysteine. A comparison of juvenile and adult brains revealed that the same cell types exist at both developmental stages, but that p and r cells increase in number and staining intensity with age. These findings are not consistent with the notion that these particular cells are the source of a "juvenile hormone' ' which has been reported to exist in nereids. Rather it is suggested that the described cells are producers of a maturation and (or) spawning hormone.

Reproductive growth in normal, allatectomized, median-neurosecretory-cell-cauterized, and ovariectomized females of Melanoplus sanguinipes

1976 ◽  
Vol 54 (2) ◽  
pp. 162-171 ◽  
Author(s):  
C. Gillott ◽  
R. H. Elliott
Keyword(s):  
Body Weight ◽  
Fat Body ◽  
Neurosecretory Cell ◽  
Initial Period ◽  
Somatic Growth ◽  
Neurosecretory Cells ◽  
Corpora Allata ◽  
Oocyte Growth ◽  
Median Neurosecretory Cells ◽  
Growth Changes

Changes in the weight of the whole insect, fat body, and ovary during successive gonotrophic cycles have been measured. The effects of ovariectomy, cautery of the median neurosecretory cells (mNSC), or removal of the corpora allata (CA) on the development of the fat body and reproductive system have also been observed.After an initial period of somatic growth, changes in body weight are very largely due to growth of the proximal oocytes and to oviposition. Yolk deposition begins when the oocytes are1.0 mm long and occurs most rapidly during the final stages of their development. Vitellogenesis begins in the penultimate oocytes when the proximal oocytes are 3.0–3.5 mm long. Ovariectomy results in a significant increase in the weight of the fat body. Removal of the CA prevents oocyte development beyond the 1-mm stage and production of secretion in the lateral oviducts. Both effects can be reversed by treating operated insects with juvenile hormone. Cautery of the mNSC, provided it is carried out within 3 h of emergence, also inhibits oocyte growth and delays the appearance of secretion in the lateral oviducts.

A neuroendocrine relationship between the nematode Hammerschmidtiella diesingi and its insect host, Blatta orientalis

Parasitology ◽  
1970 ◽  
Vol 61 (1) ◽  
pp. 101-110 ◽  
Author(s):  
R. Gordon
Keyword(s):  
Neurosecretory Cells ◽  
Corpora Allata ◽  
Insect Host ◽  
Histological Studies ◽  
Corpora Cardiaca ◽  
Blatta Orientalis ◽  
Adult Nematode ◽  
Median Neurosecretory Cells ◽  
Reproductive Processes ◽  
Terminal Oocyte

Various endocrine operations were performed on the adult female cockroach Blatta orientalis and the adult populations of the nematode Hammerschmidtiella diesingi were recorded 2 or 4 weeks later. Cautery of the median neurosecretory cells (m.n.c.) caused a significant reduction in total numbers of adult nematodes after 2 or 4 weeks; after 2 weeks, removal of the retrocerebral complex (corpora cardiaca plus corpora allata) caused a significant overall reduction in the adult nematode burden and this could not be prevented by reimplanting the corpora allata immediately after the retrocerebral complex had been removed.Anomalies appeared in the data when the sex of the parasite was examined and this may be related to a possible postembryonic mode of sex determination.Both m.n.c. cautery and removal of the retrocerebral complex suppressed host terminal oocyte development and ootheca production, whilst reimplantation of corpora allata into ‘retrocerebralectomized’ cockroaches allowed reproductive processes to continue normally. Hence, the m.n.c. and corpora allata are essential for host egg development.Histological studies showed a profound reduction in fuchsinophilic material in the corpora cardiaca of m.n.c. cauterized cockroaches.Although the m.n.c. may affect the nematode directly or indirectly, a direct effect on the parasite by the corpora allata is unlikely.

scholarly journals Venous and Arterial Endothelial Cells from Human Umbilical Cords: Potential Cell Sources for Cardiovascular Research

2021 ◽  
Vol 22 (2) ◽  
pp. 978
Author(s):  
Skadi Lau ◽  
Manfred Gossen ◽  
Andreas Lendlein ◽  
Friedrich Jung
Keyword(s):  
Endothelial Cells ◽  
Umbilical Cord ◽  
Membrane Integrity ◽  
Cell Types ◽  
Cell Number ◽  
Human Umbilical Cord ◽  
Cardiovascular Research ◽  
Cardiovascular Devices ◽  
Arterial Endothelial Cells

Although cardiovascular devices are mostly implanted in arteries or to replace arteries, in vitro studies on implant endothelialization are commonly performed with human umbilical cord-derived venous endothelial cells (HUVEC). In light of considerable differences, both morphologically and functionally, between arterial and venous endothelial cells, we here compare HUVEC and human umbilical cord-derived arterial endothelial cells (HUAEC) regarding their equivalence as an endothelial cell in vitro model for cardiovascular research. No differences were found in either for the tested parameters. The metabolic activity and lactate dehydrogenase, an indicator for the membrane integrity, slightly decreased over seven days of cultivation upon normalization to the cell number. The amount of secreted nitrite and nitrate, as well as prostacyclin per cell, also decreased slightly over time. Thromboxane B2 was secreted in constant amounts per cell at all time points. The Von Willebrand factor remained mainly intracellularly up to seven days of cultivation. In contrast, collagen and laminin were secreted into the extracellular space with increasing cell density. Based on these results one might argue that both cell types are equally suited for cardiovascular research. However, future studies should investigate further cell functionalities, and whether arterial endothelial cells from implantation-relevant areas, such as coronary arteries in the heart, are superior to umbilical cord-derived endothelial cells.

A novel epithelial cell from neonatal rat lung: isolation and differentiated phenotype

1990 ◽  
Vol 259 (6) ◽  
pp. L415-L425 ◽  
Author(s):  
P. E. Roberts ◽  
D. M. Phillips ◽  
J. P. Mather
Keyword(s):  
Epithelial Cell ◽  
Molecular Mechanisms ◽  
Basal Medium ◽  
Fold Increase ◽  
Cell Types ◽  
Cell Number ◽  
Neonatal Rat ◽  
Rat Lung ◽  
Cell Type

A novel epithelial cell from normal neonatal rat lung has been isolated, established, and maintained for multiple passages in the absence of serum, without undergoing crisis or senescence. By careful manipulation of the nutrition/hormonal microenvironment, we have been able to select, from a heterogeneous population, a single epithelial cell type that can maintain highly differentiated features in vitro. This cell type has characteristics of bronchiolar epithelial cells. A clonal line, RL-65, has been selected and observed for greater than 2 yr in continuous culture. It has been characterized by ultrastructural, morphological, and biochemical criteria. The basal medium for this cell line is Ham's F12/Dulbecco's modified Eagle's (DME) medium plus insulin (1 micrograms/ml), human transferrin (10 micrograms/ml), ethanolamine (10(-4) M), phosphoethanolamine (10(-4) M), selenium (2.5 x 10(-8) M), hydrocortisone (2.5 x 10(-7) M), and forskolin (5 microM). The addition of 150 micrograms/ml of bovine pituitary extract to the defined basal medium stimulates a greater than 10-fold increase in cell number and a 50- to 100-fold increase in thymidine incorporation. The addition of retinoic acid results in further enhancement of cell growth and complete inhibition of keratinization. We have demonstrated a strategy that may be applicable to isolating other cell types from the lung and maintaining their differentiated characteristics for long-term culture in vitro. Such a culture system promises to be a useful model in which to study cellular events associated with differentiation and proliferation in the lung and to better understand the molecular mechanisms involved in these events.

scholarly journals Cytology of the Pituitary Gonadotrophs, Histological Characteristics of Interrenal and Chromaffin Cells in Relation to Testicular Activities in Mystus Vittatus (Siluriformes, Bagridae) During Growth, Maturation and Spawning Phases

2018 ◽  
Vol 52 (2) ◽  
pp. 155-164
Author(s):  
M. Banerjee ◽  
S. Ghosh ◽  
P. Chakrabarti
Keyword(s):  
Chromaffin Cells ◽  
Cell Types ◽  
Histological Changes ◽  
Mystus Vittatus ◽  
Cytoplasmic Granules ◽  
Testicular Cells ◽  
Tsh Cells ◽  
Blue Stain ◽  
Interrenal Cells ◽  
Histological Characteristics

Abstract The histological changes observed in the pituitary corticotrophs, gonadotrophs, adrenocortical tissues and testicular cells in M. vittatus (Bloch, 1794) have been studies during growth, maturation and spawning phases. The studies based on the changes observed in the cell types, shape and size of the cells of the adrenocortical tissues, testes and the overall percentage of gonadotroph (GTH) and thyrotroph (TSH) cells of the pituitary. However, during growth phase, in proximal pars distalis (PPD) the considerable increment of GTH and TSH have been observed having intense aniline blue stain. The corticotrophs (ACTH) also showed significant accumulation of fuchsinophilic cytoplasmic granules. The cytoplasmic features and the architecture of the interrenal cells were well coincident with the increase of different spermatogenic cells. During the maturation phase dense granulation in the GTH and TSH cells appeared to be concomitant with the spermiation. The amount of cytoplasmic granules of the interrenal cells increased than chromaffin cells and was well coincidence with the increase of spermatids and spermatozoa. The hyperactive and vacuolated features of the interrenal cells during spawning phase appeared to be concomitant with the final process of spermiation.

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