scholarly journals Developmental changes in the distribution of acetylcholine receptors in the myotomes of Xenopus laevis.

1983 ◽  
Vol 339 (1) ◽  
pp. 553-571 ◽  
Author(s):  
I Chow ◽  
M W Cohen
Keyword(s):  
Xenopus Laevis ◽  
Acetylcholine Receptors ◽  
Developmental Changes

scholarly journals Developmental changes of purinergic control of intestinal motor activity during metamorphosis in the African clawed frog, Xenopus laevis

2007 ◽  
Vol 292 (5) ◽  
pp. R1916-R1925 ◽  
Author(s):  
Monika Sundqvist
Keyword(s):  
Xenopus Laevis ◽  
Motor Activity ◽  
Receptor Antagonist ◽  
Circular Muscle ◽  
Developmental Changes ◽  
Disulfonic Acid ◽  
Developmental Phase ◽  
African Clawed Frog ◽  
Low Concentrations ◽  
Clawed Frog

Little is known about the purinergic regulation of intestinal motor activity in amphibians. Purinergic control of intestinal motility is subject to changes during development in mammals. The aim of this study was to investigate purinergic control of intestinal smooth muscle in the amphibian Xenopus laevis and explore possible changes in this system during the developmental phase of metamorphosis. Effects of purinergic compounds on mean force and contraction frequency in intestinal circular muscle strips from prometamorphic, metamorphic, and juvenile animals were investigated. Before metamorphosis, low concentrations of ATP reduced motor activity, whereas the effects were reversed at higher concentrations. ATP-induced relaxation was not inhibited by the P2-receptor antagonist pyridoxalphosphate-6-azophenyl-2′,4′-disulfonic acid (PPADS) but was blocked by the ecto-nucleotidase inhibitor 6- N, N-diethyl-d-β,γ-dibromomethylene ATP ( ARL67256 ), indicating that an ATP-derived metabolite mediated the relaxation response at this stage. Adenosine induced relaxation before, during, and after metamorphosis, which was blocked by the A1-receptor antagonist 1,3-dipropyl-8-cyclopentylxanthine (DPCPX). The stable ATP-analog adenosine 5′-[γ-thio]-triphosphate (ATPγS) and 2-methylthioATP (2-MeSATP) elicited contractions in the circular muscle strips in prometamorphic tadpoles. However, in juvenile froglets, 2-MeSATP caused relaxation, as did ATPγS at low concentrations. The P2Y11/P2X1-receptor antagonist NF157 antagonized the ATPγS-induced relaxation. The P2X-preferring agonist α-β-methyleneadenosine 5′-triphosphate (α-β-MeATP) evoked PPADS-sensitive increases in mean force at all stages investigated. This study demonstrates the existence of an adenosine A1-like receptor mediating relaxation and a P2X-like receptor mediating contraction in the X. laevis gut before, during, and after metamorphosis. Furthermore, the development of a P2Y11-like receptor-mediated relaxation during metamorphosis is shown.

scholarly journals Developmental Changes in Lectin-Binding Patterns of Three Nasal Sensory Epithelia in Xenopus laevis

2011 ◽  
Vol 294 (5) ◽  
pp. 839-846 ◽  
Author(s):  
Daisuke Endo ◽  
Yoshio Yamamoto ◽  
Nobuaki Nakamuta ◽  
Kazuyuki Taniguchi
Keyword(s):  
Xenopus Laevis ◽  
Lectin Binding ◽  
Developmental Changes ◽  
Sensory Epithelia

scholarly journals Wall following in Xenopus laevis is passive

2017 ◽  
Author(s):  
Sara Hänzi ◽  
Hans Straka
Keyword(s):  
Xenopus Laevis ◽  
Shallow Water ◽  
Spatial Learning ◽  
Developmental Stages ◽  
Confounding Factor ◽  
Developmental Changes ◽  
Infrared Light ◽  
Total Distance ◽  
Summary Statement ◽  
Wall Following

AbstractThe tendency of animals to follow boundaries within their environment can serve as a strategy for spatial learning or defence. We examined whether animals of Xenopus laevis employ such a strategy by characterizing their swimming behaviour. We also investigated potential developmental changes, the influence of tentacles, which some of the developmental stages possess, and whether wall-following is active (animals seek out wall contact) or passive. Animals’ swimming movements were recorded with a camera from above in a square tank with shallow water and their trajectories were analysed especially for proximity to the nearest wall. With the exception of young larvae, in which wall following was less strong, the vast majority of animals – tadpoles and froglets – spent more time near the wall than what would be expected from the proportion of the area near the wall. The total distance covered was not a confounding factor. Wall following was also not influenced by whether the surrounding of the tank was black or white, illuminated by infrared light, or by the presence or absence of tentacles. Animals were stronger wall followers in smaller tanks. When given a choice in a convex tank to swim straight and leave the wall or turn to follow the wall, the animals consistently left the wall, indicating that wall following in Xenopus laevis is passive. This implies that wall following behaviour in Xenopus derives from constraints imposed by the environment (or the experimenter) and is unlikely a strategy for spatial learning or safety-seeking.Summary statement:Xenopus laevis tadpoles and froglets tend to swim along the walls of a square tank; but this wall following is passive – in a convex tank, they leave the wall.

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