These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Investigations on the role of cAMP in regulating resorption of the tail fin from tadpoles of Rana catesbeiana.
    Author: Ray LB, Dent JN.
    Journal: Gen Comp Endocrinol; 1986 Oct; 64(1):44-51. PubMed ID: 2435609.
    Abstract:
    Conflicting reports have appeared regarding the role of cAMP in regulating resorption of the tadpole tail during anuran metamorphosis. That cyclic nucleotide has been suggested as a mediator of the effects of both the thyroid hormones and prolactin. We tested the effects of cAMP and its derivatives dibutyryl-cAMP and 8-bromo-cAMP on explants of tail fin from tadpoles of Rana catesbeiana maintained in tissue culture. Unmodified cAMP (0.1, 2 mM) did not influence resorption. Dibutyryl-cAMP (0.1, 1 mM) and 8-bromo-cAMP (1 mM) inhibited resorption of explants induced by thyroxine (T4). The phosphodiesterase inhibitor isobutylmethylxanthine similarly inhibited regression of explants cultured with T4. None of these agents affected the increase in specific activity of hexosaminidase brought about by T4. Although the effects of cAMP in antagonizing tail resorption were similar to those of prolactin, we found no direct effect of prolactin on levels of cAMP in cultured tail fin. Thus, the effects of prolactin appear not to be mediated by increased levels of cAMP. We conclude, however, that the elevation of cellular levels of cAMP does inhibit the resorptive action of T4.
    [Abstract] [Full Text] [Related] [New Search]