SIMILAR COMPOUNDS OF ANALGESIC PEPTIDES DERIVED FROM RATTLESNAKE CROTALUS DURISSUS TERRIFICUS SNAKE VENOM, THEIR USE, COMPOSITION, PREPARATION AND PURIFICATION METHOD

The present invention relates to analogues of peptides having the amino acid sequence of SEQ ID NO: 1, SEQ ID NO: 2, SEQ ID NO: 3 or SEQ ID NO: 4, including analgesic peptides derived from species of snakes such as Crotalusdurissus terrificus; they are useful in the treatment of , their use in the diagnosis and prevention of pain conditions mediated by opioid receptors, their pharmaceutical compositions and their methods of preparation and purification, including their use in the identification of analgesic compounds.