Evidence for a new type of opioid binding site in the brain of the frog Rana ridibunda.

@article{Mollereau1988EvidenceFA,
  title={Evidence for a new type of opioid binding site in the brain of the frog Rana ridibunda.},
  author={Catherine Mollereau and A M Pascaud and Gilbert Baillat and Honor{\'e} Mazarguil and Alain Puget and J. C. Meunier},
  journal={European journal of pharmacology},
  year={1988},
  volume={150 1-2},
  pages={75-84}
}
The crude membrane fraction from the brain of the frog Rana ridibunda was shown to contain 0.7-0.8 pmol/mg protein for a site with high (KD = 0.1 nM) and about 3.2 pmol/mg protein for a site with lower (KD = 10-15 nM) affinity for the opiate agonist [3H]etorphine and for the opiate antagonist [3H]diprenorphine. In addition to its very high affinity for the two tritiated oripavine derivatives, the high affinity site displayed (i) a considerably reduced ability to bind the agonist but not the… CONTINUE READING