ULTRASTRUCTURAL STUDIES ON FORMAMIDINE-INDUCED RELEASE OF NEUROSECRETION IN LOCUSTA MIGRATORIA (ORTHOPTERA: LOCUSTIDAE)

1983 ◽  
Vol 115 (9) ◽  
pp. 1147-1153 ◽  
Author(s):  
Gur Jai Pal Singh ◽  
John F. Barker
Keyword(s):  
Plasma Membrane ◽  
Locusta Migratoria ◽  
Glandular Cell ◽  
Neurosecretory Material ◽  
Hormone Release ◽  
Corpus Cardiacum ◽  
Ultrastructural Studies ◽  
Glandular Cells

AbstractThe action of a formamidine pesticide on the ultrastructure of hormone release from the glandular lobe of the corpus cardiacum (CC) of the locust, Locusta migratoria (L.), has been studied. Treatment of the isolated CC with 5 μM desmethylchlordimeform (DCDM) caused depletion of neurosecretory material from the intrinsic cells of the glandular lobe without affecting the nervus corpus cardiacum II axons. Pretreatment of isolated CC with the α-aminergic antagonist (5 μM) phentolamine blocked DCDM-induced release of neurosecretory material from the glandular cells. DCDM-induced release of neurosecretion from the glandular cell axons occurred via exocytosis. DCDM treatment also affected the distribution of mitochondria. Mitochondria from adjacent cells lined up along the plasma membrane, forming pairs in juxtaposition.

Electron microscopy of endocardial cell populations

1978 ◽  
Vol 36 (2) ◽  
pp. 486-487
Author(s):  
T. G. Sarphie ◽  
C. R. Comer ◽  
D. J. Allen
Keyword(s):  
Electron Microscopy ◽  
Plasma Membrane ◽  
Cellular Transformation ◽  
Cell Populations ◽  
Cell Surfaces ◽  
Kb Cells ◽  
Dna Viruses ◽  
Cell Cycles ◽  
Ultrastructural Studies ◽  
Endocardial Cell

Previous ultrastructural studies have characterized surface morphology during norma cell cycles in an attempt to associate specific changes with specific metabolic processes occurring within the cell. It is now known that during the synthetic ("S") stage of the cycle, when DNA and other nuclear components are synthesized, a cel undergoes a doubling in volume that is accompanied by an increase in surface area whereby its plasma membrane is elaborated into a variety of processes originally referred to as microvilli. In addition, changes in the normal distribution of glycoproteins and polysaccharides derived from cell surfaces have been reported as depreciating after cellular transformation by RNA or DNA viruses and have been associated with the state of growth, irregardless of the rate of proliferation. More specifically, examination of the surface carbohydrate content of synchronous KB cells were shown to be markedly reduced as the cell population approached division Comparison of hamster kidney fibroblasts inhibited by vinblastin sulfate while in metaphase with those not in metaphase demonstrated an appreciable decrease in surface carbohydrate in the former.

scholarly journals Septin-dependent compartmentalization of the endoplasmic reticulum during yeast polarized growth

2005 ◽  
Vol 169 (6) ◽  
pp. 897-908 ◽  
Author(s):  
Cosima Luedeke ◽  
Stéphanie Buvelot Frei ◽  
Ivo Sbalzarini ◽  
Heinz Schwarz ◽  
Anne Spang ◽  
...  
Keyword(s):  
Endoplasmic Reticulum ◽  
Plasma Membrane ◽  
Membrane Proteins ◽  
Diffusion Barriers ◽  
Yeast Cells ◽  
Dependent Manner ◽  
Protein Diffusion ◽  
Ultrastructural Studies ◽  
Bud Neck ◽  
Er Membrane

Polarized cells frequently use diffusion barriers to separate plasma membrane domains. It is unknown whether diffusion barriers also compartmentalize intracellular organelles. We used photobleaching techniques to characterize protein diffusion in the yeast endoplasmic reticulum (ER). Although a soluble protein diffused rapidly throughout the ER lumen, diffusion of ER membrane proteins was restricted at the bud neck. Ultrastructural studies and fluorescence microscopy revealed the presence of a ring of smooth ER at the bud neck. This ER domain and the restriction of diffusion for ER membrane proteins through the bud neck depended on septin function. The membrane-associated protein Bud6 localized to the bud neck in a septin-dependent manner and was required to restrict the diffusion of ER membrane proteins. Our results indicate that Bud6 acts downstream of septins to assemble a fence in the ER membrane at the bud neck. Thus, in polarized yeast cells, diffusion barriers compartmentalize the ER and the plasma membrane along parallel lines.

The Control of Changes in Peripheral Sensilla Associated with Feeding in Locusta Migratoria (L.)

1972 ◽  
Vol 57 (3) ◽  
pp. 755-763
Author(s):  
E. A. BERNAYS ◽  
R. F. CHAPMAN
Keyword(s):  
Normal Level ◽  
Electrical Resistance ◽  
Locusta Migratoria ◽  
Corpus Cardiacum ◽  
Corpora Cardiaca ◽  
Diuretic Hormone ◽  
Stretch Receptors ◽  
The Brain ◽  
Maxillary Palps ◽  
Stimulation Of

1. The electrical resistance across the tips of the maxillary palps is not affected by stimulation of the palps, but increases to the normal level found after feeding as a result of distension of the foregut with agar or injection of corpus cardiacum homogenates into the haemolymph. 2. No increase in resistance occurs if the posterior pharyngeal nerves or the frontal connectives are cut. 3. It is inferred that distension of the foregut stimulates stretch receptors which, acting via the posterior pharyngeal nerves, the frontal connectives and the brain, cause the release of hormone from the storage lobes of the corpora cardiaca. This hormone acts on the terminal sensilla of the palps, causing them to close and so increasing the resistance across the palps. 4. Release of the diuretic hormone is controlled via the same pathway.

Secretory Structures associated with the Neurosecretory System of the Immature Scorpion, Heterometrus swammerdami

1961 ◽  
Vol s3-102 (60) ◽  
pp. 475-479
Author(s):  
MOHAMMAD HABIBULLA
Keyword(s):  
Composite Structure ◽  
Secretory Activity ◽  
Neurosecretory System ◽  
Neurosecretory Material ◽  
Corpus Cardiacum ◽  
Secretory Structures ◽  
Moult Stage ◽  
Prothoracic Glands ◽  
Frontal Ganglion ◽  
Rostral Region

Certain previously unknown structures, probably endocrine in nature, are described. The blind ‘end-organ’ which is present and shows signs of activity in the pre-moult stage shows no noticeable sign of activity in the post-moult stage. In certain respects it is comparable to the ‘anterior organ’ of spiders, which has been homologized with the prothoracic glands of insects. In the rostral region of the scorpion, where the rostral nerve ramifies, an accumulation of leucocytes is found; these show signs of secretory activity. Both at the origin of the rostral nerve and also where it ramifies, neurosecretory material is seen. This rostral structure is comparable in certain aspects with the rostral organ of spiders. Leucocytes occur not only in the rostral organ but also in association with the ‘endorgan’. The presence of two ganglionic masses, above and below the stomodaeal commissure, suggests the possibility of the sympathetic (stomatogastric) ganglion of the scorpion being a composite structure consisting of the frontal ganglion, the corpus cardiacum, and possibly the hypocerebral ganglion. A hypocerebral ganglion is absent in the adult.

Ultrastructural studies on the development and form of the principal piece sheath of the bandicoot spermatozoon

1970 ◽  
Vol 18 (1) ◽  
pp. 21 ◽  
Author(s):  
CS Sapsford ◽  
CA Rae ◽  
KW Cleland
Keyword(s):  
Plasma Membrane ◽  
Dense Material ◽  
Axial Filament ◽  
Ultrastructural Studies ◽  
The Future ◽  
Membrane Bound ◽  
End To End ◽  
Principal Piece

The first components of the sheath to develop are two longitudinal columns, characterized by alternating light and dark bands. The columns, which lie on opposite sides of the future principal piece, are initially associated with the axial filament complex but soon make contact with the plasma membrane. Subsequently a layer of moderately dense material grows outwards from the lateral aspects of each column. The outgrowths lie just beneath the tail plasma membrane and contain evenly spaced filaments which are connected with the dark bands of the columns. The outgrowths from corresponding sides of each column eventually meet each other and the filaments they contain join end-to-end. Some parts of the sheath, separated from the plasma membrane by an expansion of the cytoplasm of the intraspermatid tail, become invested by membrane bound vacuoles. The filaments form into groups, and filaments within groups converge to produce the anlagen of the ribs of the mature sheath. The filaments lose their identity in these anlagen, which, like the columns, develop much finer filamentous structures. The ribs, and subsequently the columns, lose contact with the tail plasma membrane. The mature sheath, the ultrastructure of which is described in detail, is developed by further modification of the rib anlagen and longitudinal columns.

The effect of feeding on the cerebral neurosecretory system of the adult male tsetse, Glossina austeni Newst

1978 ◽  
Vol 56 (9) ◽  
pp. 1988-1992 ◽  
Author(s):  
M. Grossman ◽  
K. G. Davey
Keyword(s):  
Adult Male ◽  
Neurosecretory Cells ◽  
Neurosecretory System ◽  
Neurosecretory Material ◽  
Corpus Cardiacum ◽  
Pars Intercerebralis ◽  
Corpora Cardiaca ◽  
Glossina Austeni ◽  
Effect Of Feeding

An analysis of the intensity of staining of the corpus cardiacum and of the neurosecretorty cells of the pars intercerebralis in 3-day-old fed or fasting adult male tsetse has revealed two periods of apparent release of neurosecretion. In fed males, stainable neurosecretion disappears from 14 of the 20 recognizable neurosecretory cells within 10 min of the termination of feeding. There is always less neurosecretory material in the corpora cardiaca of fed males. Secondly, there is an indication of a depletion of material from the cardiaca of both fed and fasted males at about 1700 hours EST.

Sign in / Sign up

Export Citation Format

Share Document