The DNA content of polytene nuclei in midgut and Malpighian tubule cells of adultDrosophila melanogaster

1982 ◽  
Vol 191 (6) ◽  
pp. 381-384 ◽  
Author(s):  
Marion J. Lamb
Keyword(s):  
Dna Content ◽  
Malpighian Tubule ◽  
Tubule Cells ◽  
Polytene Nuclei

The DNA content of testes and malpighian tubule nuclei ofTricholioproctia impatiens (Sarcophagidae, Diptera)

Chromosoma ◽  
1972 ◽  
Vol 39 (1) ◽  
pp. 83-91 ◽  
Author(s):  
Brian Roberts ◽  
Susan Roberts
Keyword(s):  
Dna Content ◽  
Malpighian Tubule

The permeability properties of septate junctions in Malpighian tubules of Rhodnius

1987 ◽  
Vol 88 (2) ◽  
pp. 251-265 ◽  
Author(s):  
H.B. Skaer ◽  
S.H. Maddrell ◽  
J.B. Harrison
Keyword(s):  
Structural Characteristics ◽  
Malpighian Tubule ◽  
Malpighian Tubules ◽  
Septate Junctions ◽  
Blood Sucking ◽  
Effects Of Ph ◽  
Intercellular Clefts ◽  
Luminal Flow ◽  
Tubule Cells ◽  
Positively Charged

This paper describes the structural characteristics and permeability properties of the smooth septate junctions between the upper Malpighian tubule cells of a blood-sucking bug, Rhodnius prolixus. The permeability of the paracellular route was tested only for solutes that could be demonstrated not to cross the epithelium via the cellular route. The intercellular clefts were readily permeated by sucrose, inulin and polyethylene glycol (PEG), showing a higher permeability to molecules of smaller radius (PEG versus sucrose). Negatively charged molecules permeated the clefts more readily than positively charged ones. The effects of pH, urea and luminal flow rate on permeability were studied. The results are discussed in relation to the physiological tightness of the Malpighian tubules to certain solutes and to its function as an excretory epithelium.

Ultrastructure of fat body cells and Malpighian tubule cells in overwintering Scoliopteryx libatrix (Noctuoidea)

PROTOPLASMA ◽  
2017 ◽  
Vol 254 (6) ◽  
pp. 2189-2199 ◽  
Author(s):  
Saška Lipovšek ◽  
Franc Janžekovič ◽  
Tone Novak
Keyword(s):  
Fat Body ◽  
Malpighian Tubule ◽  
Tubule Cells

Cytogenetic analysis of Malpighian tubule polytene chromosomes of Culex pipiens (Diptera: Culicidae)

Genome ◽  
1998 ◽  
Vol 41 (6) ◽  
pp. 751-755 ◽  
Author(s):  
Anna Zambetaki ◽  
Nicole Pasteur ◽  
Penelope Mavragani-Tsipidou
Keyword(s):  
Culex Pipiens ◽  
Polytene Chromosomes ◽  
Malpighian Tubule ◽  
Malpighian Tubules ◽  
Molecular Cytogenetic ◽  
Routine Basis ◽  
Weak Points ◽  
Chromosome Maps ◽  
Global Vector ◽  
Polytene Nuclei

A simple technique is described for obtaining well-spread and readable Malpighian tubule polytene nuclei of Culex pipiens on a routine basis. Detailed polytene chromosome maps are presented with a description of the most prominent landmarks of each chromosome, the regions with asynapsis and the most frequent weak points identified in the polytene arms. Usable Malpighian tubule polytene chromosomes should facilitate molecular cytogenetic, genetic, and potentially biosystematic studies on this medically important global vector of viral inducing encephalitis.Key words: Culex pipiens, polytene chromosomes, Malpighian tubules, banding pattern, photomap.

Intracellular ion activities in Malpighian tubule cells ofRhodnius prolixus: evaluation of Na+-K+-2Cl-cotransport across the basolateral membrane

2002 ◽  
Vol 205 (11) ◽  
pp. 1645-1655 ◽  
Author(s):  
Juan P. Ianowski ◽  
Robert J. Christensen ◽  
Michael J. O'Donnell
Keyword(s):  
Basolateral Membrane ◽  
Malpighian Tubule ◽  
Fluid Secretion ◽  
Rhodnius Prolixus ◽  
Passive Movement ◽  
Malpighian Tubules ◽  
Intracellular Ion Activities ◽  
Ion Activities ◽  
Tubule Cells ◽  
Electrochemical Potentials

SUMMARYIntracellular ion activities (aion) and basolateral membrane potential (Vbl) were measured in Malpighian tubule cells of Rhodnius prolixus using double-barrelled ion-selective microelectrodes. In saline containing 103mmoll-1Na+, 6mmoll-1 K+ and 93mmoll-1Cl-, intracellular ion activities in unstimulated upper Malpighian tubules were 21, 86 and 32mmoll-1, respectively. In serotonin-stimulated tubules, aCl was unchanged, whereas aNa increased to 33mmoll-1 and aK declined to 71mmoll-1. Vbl was -59mV and -63mV for unstimulated and stimulated tubules, respectively. Calculated electrochemical potentials(Δμ/F) favour passive movement of Na+ into the cell and passive movement of Cl- out of the cell in both unstimulated and serotonin-stimulated tubules. Passive movement of K+ out of the cell is favoured in unstimulated tubules. In stimulated tubules, Δμ/F for K+ is close to 0 mV.The thermodynamic feasibilities of Na+-K+-2Cl-, Na+-Cl-and K+-Cl- cotransporters were evaluated by calculating the net electrochemical potential (Δμnet/F) for each transporter. Our results show that a Na+-K+-2Cl- or a Na+-Cl- cotransporter but not a K+-Cl- cotransporter would permit the movement of ions into the cell in stimulated tubules. The effects of Ba2+ and ouabain on Vbl and rates of fluid and ion secretion show that net entry of K+ through ion channels or the Na+/K+-ATPase can be ruled out in stimulated tubules. Maintenance of intracellular Cl- activity was dependent upon the presence of both Na+ and K+ in the bathing saline. Bumetanide reduced the fluxes of both Na+ and K+. Taken together, the results support the involvement of a basolateral Na+-K+-2Cl- cotransporter in serotonin-stimulated fluid secretion by Rhodnius prolixus Malpighian tubules.

scholarly journals X-ray microanalysis of Rb+ entry into cricket Malpighian tubule cells via putative K+ channels

2009 ◽  
Vol 212 (18) ◽  
pp. 2977-2982 ◽  
Author(s):  
A. T. Marshall ◽  
P. L. Clode
Keyword(s):  
Malpighian Tubule ◽  
K Channels ◽  
X Ray ◽  
Tubule Cells
Sign in / Sign up

Export Citation Format

Share Document