Amphibians Pleurodeles

Preliminary investigations of the teratogenic character of MYKO 63 were performed on amphibians (pleurodeles and/or axolotls) by R. Departs, A. Jaylet and A. M. Dup-rat at the Laboratoire de Biologie Generate, Paul Sabatier University, Toulouse. The main results of their studies are as follows. 

Ethylene dibromide caused a dose-dependent increase in liver DNA alkaline-labile sites and single-strand breaks (as determined by alkaline elution assay) in female Sprague-Dawley rats. It was positive in an unscheduled DNA synthesis assay in rat spermatocytes in vitro but was negative in the spermatocytes of rats dosed in vivo. Ethylene dibromide gave positive results in an amphibian Pleurodeles yvaltl) mieronueleus test but gave negative results in dominant lethal tests. 

Pleurodeles waltl and Ambystoma mexicanum (axolotl), bred in many laboratories, were chosen because of the abundance of mucins which surround their eggs. The first analyses led to the isolation of Lewis and Lewis antigenic determinants, which are known to be related to human tumor-associated antigens. For these reasons, the jelly coats of amphibian eggs could represent a valuable model to examine 0-linked carbohydrate structures during evolution, associated with a possible function involving specific markers for the fertilization process. 

Galien (1971) investigated in detail the role of the nucleus in the development of amphibians. In his work two distinct species of the genus Pleurodeles, P, waltlii and P. poireti, were used. Through crosses the following hybrids were obtained ... 

Becker, T., Becker, C. G., Niemann, U., Naujoks, M. C., Gerardy, S. R., and Roth, G., 1993b, Amphibian-specific regulation of polysialic acid and the neural cell adhesion molecule in development and regeneration of the retinotectal system of the salamander Pleurodeles waltl, J. Comp. Neurol. 336 532-544. 

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