Stress and reproduction in Boiga irregularis with notes on the ultrastructure of the sexual segment of the kidney in squamates

2009 ◽  
Vol 87 (12) ◽  
pp. 1138-1146 ◽  
Author(s):  
D. S. Siegel ◽  
R. D. Aldridge ◽  
C. S. Clark ◽  
E. H. Poldemann ◽  
K. M. Gribbins
Keyword(s):  
Endoplasmic Reticulum ◽  
Reproductive Tract ◽  
Apical Membrane ◽  
Boiga Irregularis ◽  
Distal Nephron ◽  
Basal Nucleus ◽  
Golgi Bodies ◽  
Brown Treesnake ◽  
Histological Appearance ◽  
In Captivity

The reproductive tract of wild-caught male Boiga irregularis (Merrem, 1802) (Brown Treesnake) and the changes that result in these tissues from captivity are described. Wild-caught snakes were compared with snakes kept in captivity and sacrificed at approximately 10, 30, 50, and 60+ days. Snakes sacrificed after 10 days in captivity showed no differences in histological appearance or epithelial height in either the testis or sexual segment of the kidney (SSK) compared with wild snakes. Normal spermatogenic stages and SSK ultrastructure were observed in the testes and kidney from wild specimens and captive specimens after 10 days. In terms of the SSK, large electron-dense secretory vacuoles occupied the apices of the epithelial cells, while a basal nucleus, rough endoplasmic reticulum, and Golgi bodies filled the bases of these cells. All SSK cells were actively secretory in a mode that could most accurately be termed apocrine. At time of secretion, released vacuoles become diffuse and the apical membrane ruptures, spilling the SSK contents into the distal nephron lumen. Between 10 and 30 days in captivity, spermatogenesis and secretion in the SSK ceased and the epithelial height of both tissues decreased. At approximately 60 days, testicular epithelial height increased and spermatogenic activity was reestablished. The SSK, however, remained regressed at 60 days.

The structure and development of the spermatozoon of Dipetalonema viteae (Nematoda: Filarioidea)

Parasitology ◽  
1973 ◽  
Vol 66 (3) ◽  
pp. 447-463 ◽  
Author(s):  
Diane J. McLaren
Keyword(s):  
Electron Microscopy ◽  
Endoplasmic Reticulum ◽  
Germ Cells ◽  
Reproductive Tract ◽  
Mature Spermatozoon ◽  
Male And Female ◽  
Golgi Bodies ◽  
Male Gametes ◽  
Mammalian Spermatozoon ◽  
Dipetalonema Viteae

The structure and development of the spermatozoon of Dipetalonema viteae has been studied by means of electron microscopy. Spermatogonia are developed from a syncytium in the terminal region of the reproductive tract. The syncytium grows along the length of the testis as an anucleate rachis, carrying with it the developing germ cells. The gametes become detached from the rachis when they have become secondary spermatocytes. The chromosomes which appear in the primary spermatocytes at the onset of meiosis persist throughout all subsequent stages of development. The nucleus is not reconstructed. Cytophores are produced by the spermatids at the end of the second meiotic division. The spermatid is an elongated cell, but the mature spermatozoon, within the male tract, is amoeboid. There are only minor differences between the sperm found in the male and female tracts. The male gametes contain complex membraneous organelles which are developed from the Golgi bodies and endoplasmic reticulum of the primary spermatocytes. These organelles are suggested to have similar origins and functions to the acrosome of the typical mammalian spermatozoon.

Brown treesnake (Boiga irregularis) fact sheet for Pacific Island residents and travelers

Fact Sheet ◽  
2005 ◽  
Author(s):  
Thomas H. Fritts ◽  
D.L. Tanner ◽  
James Stanford ◽  
Teri Kman
Keyword(s):  
Pacific Island ◽  
Boiga Irregularis ◽  
Fact Sheet ◽  
Brown Treesnake

scholarly journals The pattern of appearance of enzymic activity during the development of the Golgi apparatus in amoebae

1978 ◽  
Vol 34 (1) ◽  
pp. 53-63
Author(s):  
C.J. Flickinger
Keyword(s):  
Endoplasmic Reticulum ◽  
Golgi Apparatus ◽  
Rough Endoplasmic Reticulum ◽  
Enzymic Activity ◽  
Nuclear Transplantation ◽  
Similar Distribution ◽  
Cytochemical Staining ◽  
Light Reaction ◽  
Golgi Bodies ◽  
Golgi Membranes

The appearance of enzymic activity during the development of the Golgi apparatus was studied by cytochemical staining of renucleated amoebae. In cells enucleated for 4 days, there was a great decline in size and number of Golgi bodies, or dictyosomes. Subsequent renucleation by nuclear transplantation resulted in a regeneration of Golgi bodies. Samples of amoebae were fixed and incubated for cytochemical staining at intervals of 1, 6, or 24 h after renucleation. Enzymes selected for study were guanosine diphosphatase (GDPase), esterase, and thiamine pyrophosphatase (TPPase). All three were found in the Golgi apparatus of normal amoebae but they differed in their overall intracellular distribution. GDPase was normally present at the convex pole of the Golgi apparatus, in rough endoplasmic reticulum, and in the nuclear envelope. In amoebae renucleated for 1 h, light reaction product for GDPase was present throughout the small stacks of cisternae that represented the forming Golgi apparatus. By 6 h following the operation GDPase reaction product was concentrated at the convex pole of the Golgi apparatus. Esterase, which was distributed throughout the stacks of normal Golgi cisternae, displayed a similar distribution in the forming Golgi bodies as soon as they were visible. TPPase was normally present in the Golgi apparatus but was not found in the endoplasmic reticulum. In contrast to the other enzymes, TPPase reaction product was absent from the forming Golgi apparatus 1 and 6 h after renucleation, and did not appear in the Golgi apparatus until 24 h after operation. Thus, enzymes held in common between the rough endoplasmic reticulum and the Golgi apparatus were present in the forming Golgi apparatus as soon as it was detectable, but an enzyme cytochemically localized to the Golgi apparatus only appeared later in development of the organelle. It is suggested that Golgi membranes might be derived from the endoplasmic reticulum and thus immediately contain endoplasmic reticulum enzymes, while Golgi-specific enzymes are added later in development.

scholarly journals Experimental landscape reduction of wild rodents increases movements in the invasive brown treesnake (Boiga irregularis)

2017 ◽  
Vol 8 (4) ◽  
pp. 455-467 ◽  
Author(s):  
Michelle Christy ◽  
Julie Savidge ◽  
Amy Yackel Adams ◽  
James Gragg ◽  
Gordon Rodda
Keyword(s):  
Boiga Irregularis ◽  
Wild Rodents ◽  
Brown Treesnake

Distribution of transcellular calcium and sodium transport pathways along mouse distal nephron

2001 ◽  
Vol 281 (6) ◽  
pp. F1021-F1027 ◽  
Author(s):  
Johannes Loffing ◽  
Dominique Loffing-Cueni ◽  
Victor Valderrabano ◽  
Lea Kläusli ◽  
Steven C. Hebert ◽  
...  
Keyword(s):  
Apical Membrane ◽  
Binding Protein ◽  
Collecting Duct ◽  
Transport Proteins ◽  
Distal Nephron ◽  
Transport Pathways ◽  
Transport Regulation ◽  
Low Levels ◽  
Calbindin D ◽  
Distal Convolution

First published August 15, 2001; 10.1152/ajprenal. 00085.2001.—The organization of Na+ and Ca2+ transport pathways along the mouse distal nephron is incompletely known. We revealed by immunohistochemistry a set of Ca2+ and Na+transport proteins along the mouse distal convolution. The thiazide-sensitive Na+-Cl− cotransporter (NCC) characterized the distal convoluted tubule (DCT). The amiloride-sensitive epithelial Na+ channel (ENaC) colocalized with NCC in late DCT (DCT2) and extended to the downstream connecting tubule (CNT) and collecting duct (CD). In early DCT (DCT1), the basolateral Ca2+-extruding proteins [Na+/Ca2+ exchanger (NCX), plasma membrane Ca2+-ATPase (PCMA)] and the cytoplasmic Ca2+-binding protein calbindin D28K (CB) were found at very low levels, whereas the cytoplasmic Ca2+/Mg2+-binding protein parvalbumin was highly abundant. NCX, PMCA, and CB prevailed in DCT2 and CNT, where we located the apical epithelial Ca2+ channel (ECaC1). Its subcellular localization changed from apical in DCT2 to exclusively cytoplasmic at the end of CNT. NCX and PMCA decreased in parallel with the fading of ECaC1 in the apical membrane. All three of them were undetectable in CD. These findings disclose DCT2 and CNT as major sites for transcellular Ca2+ transport in the mouse distal nephron. Cellular colocalization of Ca2+ and Na+ transport pathways suggests their mutual interactions in transport regulation.

Model explaining the relation between distal nephron Li+ reabsorption and urinary Na+ excretion in rats

1998 ◽  
Vol 274 (3) ◽  
pp. F445-F452 ◽  
Author(s):  
Michael Shalmi ◽  
Thomas Jonassen ◽  
Klaus Thomsen ◽  
Jonathan D. Kibble ◽  
Peter Bie ◽  
...  
Keyword(s):  
Urinary Excretion ◽  
Apical Membrane ◽  
Fractional Excretion ◽  
Distal Nephron ◽  
Conscious Rats ◽  
Angiotensin Iii ◽  
Collecting Ducts ◽  
Induced Changes ◽  
Different Levels

Li+ may be reabsorbed via an amiloride-sensitive mechanism in the collecting ducts of rats administered a low-Na+ diet. This was investigated by measuring the increase in fractional urinary excretion of Li+(FELi) in response to amiloride in conscious rats at two different levels of plasma Li+ concentration and after administration of bendroflumethiazide (BFTZ), angiotensin III (ANG III), and aldosterone (Aldo). The results confirmed that amiloride increased (FELi) in rats on a low-Na+ diet (20 ± 1 to 35 ± 1%, means ± SE), whereas no increase was observed in rats on a normal Na+ diet (37 ± 1 to 38 ± 1%). The lithiuretic effect of amiloride was 1) abolished by preadministration of BFTZ (32 ± 1 to 33 ± 2%) to Na+-deprived rats and 2) increased by ANG III (27 ± 3 to 33 ± 2%) and Aldo (25 ± 2 to 37 ± 2%) in Na+-replete rats. Amiloride-induced changes in FELiwere independent of plasma Li+concentration but inversely related to the fractional excretion of Na+ and the amiloride-sensitive excretion of K+. These results are compatible with the hypothesis that a low tubular Na+ concentration reduces end-tubular Na+ reabsorption and results in hyperpolarization of the apical membrane, thus favoring Li+ uptake into the cells.

CHANGES IN CELL FINE STRUCTURE OF LIMA BEAN AXES DURING EARLY GERMINATION

1966 ◽  
Vol 44 (3) ◽  
pp. 331-340 ◽  
Author(s):  
Shimon Klein ◽  
Yehuda Ben-Shaul
Keyword(s):  
Endoplasmic Reticulum ◽  
Fine Structure ◽  
Cell Walls ◽  
Lipid Droplets ◽  
Lima Bean ◽  
Amorphous Substance ◽  
Golgi Bodies ◽  
Early Germination ◽  
Almost All ◽  
Vacuolar Content

Changes in cell fine structure were studied in axes of green lima bean seeds soaked in water for 1–48 hours. At the beginning of the imbibition period the cortical and pith cells and to a smaller degree the cells of the future conductive tissues contain several vacuoles filled with an amorphous substance. Almost all of the cells contain lipid droplets arranged exclusively along cell walls. The endoplasmic reticulum appears in the form of long tubules, predominantly occupying the peripheral parts of the cell, surrounding the nucleus. A large concentration of ribosomes, mostly unattached, can be found in the cytoplasm. Similar particles make up the bulk of the nucleolus, but could not be found in plastids, which frequently contained starch, but were devoid of internal membranes. Only very few Golgi bodies occur. No changes in fine structure seem to occur during the first 4 hours of imbibition, but after 24 hours the lipid droplets and the vacuolar content have disappeared, the endoplasmic reticulum is more evenly distributed throughout the cells, and a large number of Golgi bodies can be seen.

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